Well-Program Economics — Scenario Table, NPV, IRR, Payout

The economics of a small Texas horizontal program (5–10 wells), modelled month by month, with one scenario per row of an Excel Table. Each row carries its assumptions — prices, D&C, LOE, type-curve factor, well count, working and net revenue interest, discount rate — and, in the same row, its NPV, IRR, payout, PV/I, EUR per well and net cash. Change a row or add one at the bottom and its results fill in. The default assumptions are illustrative, not a price deck.

Well-Program Economics Excel workbook

WellProgramEconomics.xlsx

Well-Program Economics — Scenario Table, NPV, IRR, Payout: NPV by scenario ($MM) (Scenarios)

Well-Program Economics — Scenario Table, NPV, IRR, Payout: Cumulative net cash flow ($MM) (Cash Flow)

Well-Program Economics — Scenario Table, NPV, IRR, Payout: Guide sheet

Well-Program Economics — Scenario Table, NPV, IRR, Payout: Assumptions sheet

Well-Program Economics — Scenario Table, NPV, IRR, Payout: Scenarios sheet

Well-Program Economics — Scenario Table, NPV, IRR, Payout: Cash Flow sheet

Description Preview Requirements

Wells come online one every few months and are drilled the month before. Each follows an Arps hyperbolic type curve switching to an exponential terminal decline, sampled at mid-month, with gas from a constant GOR, and produces until its operating margin reaches zero (the economic limit) or a life cap, then is plugged. Net revenue is the NRI share; Texas severance (4.6 % oil, 7.5 % gas) is charged on the oil and gas value and ad valorem on net revenue; costs and capital are the WI share. IRR is the monthly IRR annualised, found by bracketing the economic root so that the spurious negative root a plugging cost creates at low prices is not mistaken for it.

A partner is a row: its own WI and NRI scale the costs and the revenue, so a 40 % partner at the same revenue-to-working-interest ratio earns exactly 40 % of the base NPV. One annual escalation rate applies to prices and operating costs. Price decks, risked or Monte Carlo economics, reserves booking and fiscal regimes beyond the Texas taxes are not in version 1.

The Cash Flow sheet is the audit of one case, picked by number on the Scenarios sheet: the program year by year, from the same monthly engine, with lines that show the annual rows reconcile to it.

The engine is workbook LAMBDAs, named in the catalog's style so they can be promoted: PO.ECON.Arps.Di, PO.ECON.Arps.Rate, PO.ECON.Arps.Time, PO.ECON.NPV.Monthly, PO.ECON.IRR.Monthly and PO.ECON.Payout, and the MODEL.* functions that bind this workbook's assumptions.

Inputs

Named cells you can edit — every result recalculates from them. A Scenarios row can override any of its assumption columns with a number or a formula.

Name	Description	Default	Unit
`EC_Wells`	Wells in the program	8	wells
`EC_FirstOnline`, `EC_Spacing`	First well online, months between wells	3, 1	month, months
`EC_LifeCap`	Longest producing life of a well	360	months
`EC_IP`	Initial oil rate, one well	800	bbl/d
`EC_b`, `EC_Dei`, `EC_Dterm`	Arps exponent, initial and terminal decline	1.0, 65 %, 8 %	—, per year
`EC_GOR`, `EC_TC`	Gas–oil ratio, type-curve factor	1500, 1.0	scf/bbl, ×
`EC_Oil`, `EC_OilDiff`, `EC_Gas`, `EC_GasDiff`	Prices and differentials	70, 1.5, 3.0, 1.0	$/bbl, $/MMBtu
`EC_Esc`	Escalation, prices and operating costs	0 %	per year
`EC_WI`, `EC_NRI`	Working and net revenue interest	100 %, 75 %	—
`EC_SevOil`, `EC_SevGas`, `EC_AdVal`	Texas severance and ad valorem taxes	4.6 %, 7.5 %, 2.5 %	of value
`EC_DC`	Drilling and completion, per well	7.0	$MM
`EC_LOE`, `EC_LOEVar`, `EC_Gath`, `EC_PA`	Fixed LOE, variable LOE, gathering, plugging	8000, 4, 0.5, 150000	$/well-month, $/bbl, $/Mcf, $
`EC_Disc`, `EC_Hurdle`	Discount rate, IRR hurdle	10 %, 15 %	per year
`EC_Pick`	Case shown on Cash Flow (0 = base case)	0	—

4 sheets, shown with the values the file opens with

	A
1	Well-program economics — one scenario per row
2
3	What this is
4	The economics of a small Texas horizontal program (5–10 wells), modelled month by month. An Excel Table holds one scenario per row: its assumptions, and in the same row its NPV, IRR, payout, PV/I, EUR and net cash. Change a row, or add one, and its results follow. The default assumptions are illustrative, not a price deck. Every formula is plain Excel; no add-in is needed.
5
6	Sheets
7	Assumptions — the base case. Blue cells on a yellow background are inputs: program, type curve, prices, interests, Texas severance (4.6 % oil, 7.5 % gas) and ad valorem, costs and the discount rate.
8	Scenarios — the Table. An assumption cell is a number or a formula on the base case, so a row that does not override a value follows the Assumptions sheet. Result columns are calculated columns calling named LAMBDAs (Formulas › Name Manager, MODEL.* and PO.ECON.*) that run the whole monthly model on that row's assumptions. The picker at the top (C2) sends any row to Cash Flow.
9	Cash Flow — the audit of one case: the program year by year (volumes, revenue, taxes, costs, capital, net and discounted cash, cumulative), for the base case or the row picked on Scenarios. The annual rows are sums of the same monthly engine, and the sheet shows that they reconcile to it.
10
11	The model
12	Wells come online one every few months and are drilled the month before. Each well follows an Arps hyperbolic type curve switching to an exponential terminal decline, sampled at mid-month, with gas from a constant GOR. A well produces until its operating margin reaches zero (the economic limit, from start-of-life prices) or the life cap, then is plugged the following month. Net revenue is the NRI share; severance is charged on the oil and gas value and ad valorem on net revenue; costs and capital are the WI share. NPV discounts end-of-month cash flows at the annual rate; IRR is the monthly IRR annualised; PV/I is NPV divided by the discounted capital.
13
14	What version 1 takes in, and what it leaves out
15	Escalation is in: one annual rate on prices and operating costs (Assumptions), applied month by month. Partners are in as rows: a partner's case is a row with its own WI and NRI, which scales the costs by WI and the revenue by NRI — a 40 % partner at the same revenue-to-working-interest ratio earns exactly 40 % of the base NPV. Price decks are out: a deck is a table of prices per scenario, which does not fit one row, so a scenario has flat prices (plus escalation).
16	Also out: risked or Monte Carlo economics, reserves booking, fiscal regimes beyond the Texas taxes shown, and any carry or reversion in the interests.
17
18	Reading the results
19	Negative NPV, and an IRR below the hurdle or with no root, are flagged red in the Table. IRR is "n/a" when NPV never falls through zero between −5 % and +45 % a month; payout is "none" when cumulative cash never recovers. The Cash Flow sheet shows 35 years; a program that runs longer says so there, but the Table always uses the whole life.

	A	B	C	D
1	Assumptions — base case
2	Blue cells on a yellow background are inputs. Illustrative defaults for a small Texas horizontal program; the Scenarios sheet varies price, capital, LOE, type curve, well count, interests and discount rate around them.
3
4	Program
5	Wells	8	wells	1–10 (a small program is 5–10); each is drilled the month before it comes online
6	First well online	3	month	Month 1 is the start of the program; 2 or later
7	Months between wells coming online	1	months
8	Longest producing life of a well	360	months	A well stops sooner when its margin reaches zero
9
10	Type curve — one well, oil
11	Initial oil rate	800	bbl/d
12	Arps hyperbolic exponent b	1.00	—	0 < b ≤ 2
13	Initial decline, effective secant	65%	per year
14	Terminal decline, effective	8%	per year	Exponential tail after the switch
15	Gas–oil ratio	1,500	scf/bbl	Constant over life
16	Type-curve factor	1.00	×	Scales the initial rate: 0.75 ≈ P90, 1.3 ≈ P10
17
18	Prices
19	Oil price (WTI)	70.00	$/bbl
20	Oil differential	1.50	$/bbl	Deducted: quality and transport
21	Gas price (Henry Hub)	3.00	$/MMBtu	1 MMBtu per Mcf assumed
22	Gas differential	1.00	$/MMBtu	Deducted: Waha basis
23	Escalation, prices and operating costs	0.0%	per year	The economic limit uses start-of-life prices
24
25	Interests and Texas taxes
26	Working interest	100.0%		Scales costs and capital
27	Net revenue interest	75.0%		Scales revenue; 25 % royalty at 100 % WI
28	Oil production (severance) tax	4.6%	of value	Texas: 4.6 % of the market value of oil
29	Gas production (severance) tax	7.5%	of value	Texas: 7.5 % of the market value of gas
30	Ad valorem tax	2.5%	of revenue	Approximated as a share of net revenue
31
32	Costs
33	Drilling and completion, per well	7.00	$MM	Spent the month before the well comes online
34	Fixed LOE	8,000	$/well-month
35	Variable LOE	4.00	$/bbl
36	Gas gathering and processing	0.50	$/Mcf
37	Plugging and abandonment, per well	150,000	$	The month after the well's last production
38
39	Discounting
40	Discount rate	10.0%	per year	End-of-month cash flows; NPV at this rate
41	IRR hurdle	15.0%	per year	IRR below this is flagged red on the Scenarios sheet

	A	B	C	D	E	F	G	H	I	J	K	L	M	N	O	P	Q
1	Scenarios — one row per set of assumptions, results in the same row
2		Case shown on the Cash Flow sheet:	0	0 = the base case on the Assumptions sheet; otherwise a Case number from the Table (found by number, so sorting is safe).
3	Assumption columns (blue) are inputs — numbers, or formulas on the base case so they follow it. Result columns are calculated columns calling the MODEL.* and PO.ECON.* LAMBDAs, so every row runs the whole monthly model on its own assumptions. Add a row at the bottom of the Table and its results fill in. WI scales costs and capital, NRI scales revenue: a partner is a row.
4
5	Case	Scenario	Oil $/bbl	Gas $/MMBtu	D&C $MM/well	LOE $/well-month	Type curve factor	Wells	WI	NRI	Discount rate	NPV $MM	IRR	Payout months	PV/I	EUR Mbbl/well	Net cash $MM
6	1	Base case	70.00	3.00	7.00	8,000	1.00	8	100.0%	75.0%	10.0%	76.2	112.5%	17	1.42	612	140.1
7	2	Low oil — $55	55.00	3.00	7.00	8,000	1.00	8	100.0%	75.0%	10.0%	44.4	57.8%	24	0.83	612	88.9
8	3	High oil — $85	85.00	3.00	7.00	8,000	1.00	8	100.0%	75.0%	10.0%	108.1	190.3%	14	2.02	612	191.2
9	4	Low gas — $1.50	70.00	1.50	7.00	8,000	1.00	8	100.0%	75.0%	10.0%	71.6	103.2%	18	1.34	612	132.6
10	5	D&C +20 %	70.00	3.00	8.40	8,000	1.00	8	100.0%	75.0%	10.0%	65.5	72.0%	21	1.02	612	128.9
11	6	D&C −15 %	70.00	3.00	5.95	8,000	1.00	8	100.0%	75.0%	10.0%	84.3	168.1%	15	1.85	612	148.5
12	7	LOE +25 %	70.00	3.00	7.00	10,000	1.00	8	100.0%	75.0%	10.0%	74.4	111.2%	17	1.39	612	134.3
13	8	P90 type curve (×0.75)	70.00	3.00	7.00	8,000	0.75	8	100.0%	75.0%	10.0%	41.9	54.4%	24	0.78	458	85.0
14	9	P10 type curve (×1.30)	70.00	3.00	7.00	8,000	1.30	8	100.0%	75.0%	10.0%	117.4	218.4%	14	2.19	796	206.2
15	10	5 wells	70.00	3.00	7.00	8,000	1.00	5	100.0%	75.0%	10.0%	48.2	112.5%	16	1.42	612	87.5
16	11	10 wells	70.00	3.00	7.00	8,000	1.00	10	100.0%	75.0%	10.0%	94.5	112.5%	18	1.42	612	175.1
17	12	8 % discount rate	70.00	3.00	7.00	8,000	1.00	8	100.0%	75.0%	8.0%	84.5	112.5%	17	1.56	612	140.1
18	13	12 % discount rate	70.00	3.00	7.00	8,000	1.00	8	100.0%	75.0%	12.0%	69.2	112.5%	17	1.30	612	140.1
19	14	Downside — $50 oil, P90, D&C +20 %, LOE +25 %	50.00	1.50	8.40	10,000	0.75	8	100.0%	75.0%	10.0%	-5.8	6.0%	92	-0.09	435	13.3
20	15	40 % partner — WI 40 %, NRI in proportion	70.00	3.00	7.00	8,000	1.00	8	40.0%	30.0%	10.0%	30.5	112.5%	17	1.42	612	56.0
21
22
23
24
25

NPV at each row's discount rate ($MM)

	A	B	C	D	E	F	G	H	I	J	K	L
1	Cash flow — base case
2	The case picked on the Scenarios sheet (0 = base case), year by year. The annual rows are sums of the same monthly engine the Table uses.
3
4	Case shown (picked on the Scenarios sheet)						Results — the case shown
5	Table row of the picked case			0			NPV			76.2	$MM
6	Oil price			70.00	$/bbl		IRR			112.5%	per year
7	Gas price			3.00	$/MMBtu		Payout			17	months
8	D&C per well			7.00	$MM		PV/I			1.42	NPV ÷ disc. capital
9	Fixed LOE			8,000	$/well-month		EUR per well			612	Mbbl
10	Type-curve factor			1.00	×		Net cash			140.1	$MM, undiscounted
11	Wells			8	wells		Producing life of a well			360	months
12	Working interest			100.0%			Years shown			every well's life fits
13	Net revenue interest			75.0%			Annual rows − monthly engine, NPV			0.000000
14	Discount rate			10.0%	per year		Annual rows − monthly engine, net cash			-0.000000
15
16
17	Year	Average wells producing	Oil (Mbbl)	Gas (MMcf)	Net revenue ($MM)	Severance + ad valorem ($MM)	Operating cost ($MM)	Capital ($MM)	P&A ($MM)	Net cash ($MM)	Discounted ($MM)	Cumulative ($MM)
18	1	4.3	855	1,283	45.9	3.3	4.5	56.0	0.0	-17.9	-18.0	-17.9
19	2	8.0	840	1,259	45.0	3.3	4.8	0.0	0.0	37.0	32.1	19.1
20	3	8.0	497	745	26.6	1.9	3.1	0.0	0.0	21.6	17.0	40.7
21	4	8.0	355	532	19.0	1.4	2.5	0.0	0.0	15.2	10.9	55.9
22	5	8.0	276	415	14.8	1.1	2.1	0.0	0.0	11.7	7.6	67.5
23	6	8.0	226	340	12.1	0.9	1.8	0.0	0.0	9.4	5.6	77.0
24	7	8.0	192	288	10.3	0.7	1.7	0.0	0.0	7.9	4.2	84.8
25	8	8.0	166	250	8.9	0.6	1.6	0.0	0.0	6.7	3.3	91.6
26	9	8.0	147	220	7.9	0.6	1.5	0.0	0.0	5.8	2.6	97.4
27	10	8.0	132	197	7.1	0.5	1.4	0.0	0.0	5.2	2.1	102.6
28	11	8.0	119	179	6.4	0.5	1.3	0.0	0.0	4.6	1.7	107.1
29	12	8.0	109	163	5.8	0.4	1.3	0.0	0.0	4.1	1.4	111.3
30	13	8.0	100	150	5.4	0.4	1.2	0.0	0.0	3.7	1.1	115.0
31	14	8.0	92	138	4.9	0.4	1.2	0.0	0.0	3.4	0.9	118.4
32	15	8.0	85	127	4.5	0.3	1.2	0.0	0.0	3.0	0.8	121.4
33	16	8.0	78	117	4.2	0.3	1.1	0.0	0.0	2.7	0.6	124.2
34	17	8.0	72	107	3.8	0.3	1.1	0.0	0.0	2.5	0.5	126.6
35	18	8.0	66	99	3.5	0.3	1.1	0.0	0.0	2.2	0.4	128.8
36	19	8.0	61	91	3.3	0.2	1.1	0.0	0.0	2.0	0.3	130.8
37	20	8.0	56	84	3.0	0.2	1.0	0.0	0.0	1.7	0.3	132.5
38	21	8.0	51	77	2.8	0.2	1.0	0.0	0.0	1.5	0.2	134.0
39	22	8.0	47	71	2.5	0.2	1.0	0.0	0.0	1.4	0.2	135.4
40	23	8.0	43	65	2.3	0.2	1.0	0.0	0.0	1.2	0.1	136.6
41	24	8.0	40	60	2.1	0.2	1.0	0.0	0.0	1.0	0.1	137.6
42	25	8.0	37	55	2.0	0.1	0.9	0.0	0.0	0.9	0.1	138.5
43	26	8.0	34	51	1.8	0.1	0.9	0.0	0.0	0.8	0.1	139.3
44	27	8.0	31	47	1.7	0.1	0.9	0.0	0.0	0.6	0.1	139.9
45	28	8.0	29	43	1.5	0.1	0.9	0.0	0.0	0.5	0.0	140.4
46	29	8.0	26	40	1.4	0.1	0.9	0.0	0.0	0.4	0.0	140.8
47	30	8.0	24	36	1.3	0.1	0.9	0.0	0.0	0.3	0.0	141.2
48	31	3.7	10	16	0.6	0.0	0.4	0.0	1.2	-1.1	-0.1	140.1
49	32	0.0	0	0	0.0	0.0	0.0	0.0	0.0	0.0	0.0	140.1
50	33	0.0	0	0	0.0	0.0	0.0	0.0	0.0	0.0	0.0	140.1
51	34	0.0	0	0	0.0	0.0	0.0	0.0	0.0	0.0	0.0	140.1
52	35	0.0	0	0	0.0	0.0	0.0	0.0	0.0	0.0	0.0	140.1
53	Total		4,896	7,343	262.5	19.0	46.3	56.0	1.2	140.1	76.2

Cumulative net cash flow

Name	Refers To	Comment
MODEL.Annual	=LAMBDA(oil_price,gas_price,dc_mm,loe_fixed,tc_factor,well_count,wi_frac,nri_frac,disc_rate,year_count,LET(monthly_matrix,MODEL.Monthly(oil_price,gas_price,dc_mm,loe_fixed,tc_factor,well_count,wi_frac,nri_frac),month_no,CHOOSECOLS(monthly_matrix,1),net_cash,CHOOSECOLS(monthly_matrix,5)-CHOOSECOLS(monthly_matrix,6)-CHOOSECOLS(monthly_matrix,7)-CHOOSECOLS(monthly_matrix,8)-CHOOSECOLS(monthly_matrix,9),scaled,HSTACK(CHOOSECOLS(monthly_matrix,2)/12,CHOOSECOLS(monthly_matrix,3)/1000,CHOOSECOLS(monthly_matrix,4)/1000,CHOOSECOLS(monthly_matrix,5)/1000000,CHOOSECOLS(monthly_matrix,6)/1000000,CHOOSECOLS(monthly_matrix,7)/1000000,CHOOSECOLS(monthly_matrix,8)/1000000,CHOOSECOLS(monthly_matrix,9)/1000000,net_cash/1000000,net_cash/(1+disc_rate)^(month_no/12)/1000000),in_year,(month_no>12(SEQUENCE(1,year_count)-1))(month_no<=12*SEQUENCE(1,year_count)),HSTACK(SEQUENCE(year_count),MMULT(TRANSPOSE(in_year),scaled))))
MODEL.Capex	=LAMBDA(dc_mm,well_count,wi_frac,LET(month,SEQUENCE(EC_FirstOnline+(well_count-1)EC_Spacing+EC_LifeCap+1),online,EC_FirstOnline+(SEQUENCE(1,well_count)-1)EC_Spacing,dc_mm1000000wi_fracMMULT((month=online-1)1,SEQUENCE(well_count,1,1,0))))
MODEL.CashFlow	=LAMBDA(oil_price,gas_price,dc_mm,loe_fixed,tc_factor,well_count,wi_frac,nri_frac,LET(monthly_matrix,MODEL.Monthly(oil_price,gas_price,dc_mm,loe_fixed,tc_factor,well_count,wi_frac,nri_frac),CHOOSECOLS(monthly_matrix,5)-CHOOSECOLS(monthly_matrix,6)-CHOOSECOLS(monthly_matrix,7)-CHOOSECOLS(monthly_matrix,8)-CHOOSECOLS(monthly_matrix,9)))
MODEL.EUR	=LAMBDA(oil_price,gas_price,loe_fixed,tc_factor,wi_frac,nri_frac,LET(q_init,EC_IPtc_factor,d_init,PO.ECON.Arps.Di(EC_b,EC_Dei),d_term,-LN(1-EC_Dterm),life_months,MODEL.Life(q_init,oil_price,gas_price,loe_fixed,wi_frac,nri_frac),IF(life_months=0,0,SUM(PO.ECON.Arps.Rate(q_init,EC_b,d_init,d_term,(SEQUENCE(life_months)-0.5)/12))30.4375)))
MODEL.Life	=LAMBDA(q_init,oil_price,gas_price,loe_fixed,wi_frac,nri_frac,LET(d_init,PO.ECON.Arps.Di(EC_b,EC_Dei),d_term,-LN(1-EC_Dterm),margin,(oil_price-EC_OilDiff)nri_frac(1-EC_SevOil-EC_AdVal)+EC_GOR/1000((gas_price-EC_GasDiff)nri_frac(1-EC_SevGas-EC_AdVal)-EC_Gathwi_frac)-EC_LOEVarwi_frac,IF(margin<=0,0,IF(loe_fixed<=0,EC_LifeCap,MIN(EC_LifeCap,INT(12PO.ECON.Arps.Time(q_init,EC_b,d_init,d_term,loe_fixedwi_frac/(30.4375margin))))))))
MODEL.Monthly	=LAMBDA(oil_price,gas_price,dc_mm,loe_fixed,tc_factor,well_count,wi_frac,nri_frac,LET(q_init,EC_IPtc_factor,d_init,PO.ECON.Arps.Di(EC_b,EC_Dei),d_term,-LN(1-EC_Dterm),life_months,MODEL.Life(q_init,oil_price,gas_price,loe_fixed,wi_frac,nri_frac),month,SEQUENCE(EC_FirstOnline+(well_count-1)EC_Spacing+EC_LifeCap+1),online,EC_FirstOnline+(SEQUENCE(1,well_count)-1)EC_Spacing,well_age,month-online+1,producing,(well_age>=1)(well_age<=life_months),t_years,((well_age>=1)well_age+(well_age<1)-0.5)/12,ones_col,SEQUENCE(well_count,1,1,0),oil_bbl,MMULT(producingPO.ECON.Arps.Rate(q_init,EC_b,d_init,d_term,t_years)30.4375,ones_col),wells_on,MMULT(producing,ones_col),gas_mcf,oil_bblEC_GOR/1000,escalation,(1+EC_Esc)^((month-1)/12),net_oil,oil_bbl(oil_price-EC_OilDiff)escalationnri_frac,net_gas,gas_mcf(gas_price-EC_GasDiff)escalationnri_frac,taxes,net_oilEC_SevOil+net_gasEC_SevGas+(net_oil+net_gas)EC_AdVal,op_cost,(loe_fixedwells_on+EC_LOEVaroil_bbl+EC_Gathgas_mcf)wi_fracescalation,plugging,EC_PAwi_fracMMULT((month=online+life_months)*1,ones_col),HSTACK(month,wells_on,oil_bbl,gas_mcf,net_oil+net_gas,taxes,op_cost,MODEL.Capex(dc_mm,well_count,wi_frac),plugging)))
PO.ECON.Arps.Di	=LAMBDA(b_exp,d_secant,1/b_exp*((1-d_secant)^(-b_exp)-1))
PO.ECON.Arps.Rate	=LAMBDA(q_init,b_exp,d_init,d_term,t_years,LET(t_switch,MAX(0,(d_init/d_term-1)/(b_expd_init)),q_switch,q_init(1+b_expd_initt_switch)^(-1/b_exp),(t_years<=t_switch)q_init(1+b_expd_initt_years)^(-1/b_exp)+(t_years>t_switch)q_switchEXP(-d_term*(t_years-t_switch))))
PO.ECON.Arps.Time	=LAMBDA(q_init,b_exp,d_init,d_term,q_limit,LET(t_switch,MAX(0,(d_init/d_term-1)/(b_expd_init)),q_switch,q_init(1+b_expd_initt_switch)^(-1/b_exp),IF(q_limit>=q_init,0,IF(q_limit>=q_switch,((q_init/q_limit)^b_exp-1)/(b_exp*d_init),t_switch+LN(q_switch/q_limit)/d_term))))
PO.ECON.IRR.Monthly	=LAMBDA(cash,LET(cash_col,cash,grid_step,0.0025,rates,SEQUENCE(1,201,-0.05,grid_step),periods,SEQUENCE(ROWS(cash_col)),npv_grid,MMULT(TRANSPOSE(cash_col),(1+rates)^(-periods)),first_pos,IFERROR(XMATCH(TRUE,npv_grid>0),0),crossing,IF(first_pos=0,0,IFERROR(XMATCH(1,(SEQUENCE(1,201)>first_pos)(npv_grid<=0)),0)),IF(crossing=0,"n/a",LET(r_lo,INDEX(rates,1,crossing-1),v_lo,INDEX(npv_grid,1,crossing-1),v_hi,INDEX(npv_grid,1,crossing),r_interp,r_lo+grid_stepv_lo/(v_lo-v_hi),r_refined,IFERROR(IRR(cash_col,r_lo),r_interp),(1+IF(AND(r_refined>=r_lo,r_refined<=r_lo+grid_step),r_refined,r_interp))^12-1))))
PO.ECON.NPV.Monthly	=LAMBDA(cash,annual_rate,NPV((1+annual_rate)^(1/12)-1,cash))
PO.ECON.Payout	=LAMBDA(cash,LET(cumulative,SCAN(0,cash,LAMBDA(running,flow,running+flow)),trough,MATCH(MIN(cumulative),cumulative,0),IFERROR(MATCH(1,(SEQUENCE(ROWS(cumulative))>trough)*(cumulative>=0),0),"none")))
CF_DC	'Cash Flow'!$D$8
CF_Disc	'Cash Flow'!$D$14
CF_EUR	'Cash Flow'!$J$9
CF_Gas	'Cash Flow'!$D$7
CF_IRR	'Cash Flow'!$J$6
CF_LOE	'Cash Flow'!$D$9
CF_Life	'Cash Flow'!$J$11
CF_NPV	'Cash Flow'!$J$5
CF_NRI	'Cash Flow'!$D$13
CF_NetCash	'Cash Flow'!$J$10
CF_Oil	'Cash Flow'!$D$6
CF_PVI	'Cash Flow'!$J$8
CF_Payout	'Cash Flow'!$J$7
CF_ReconNet	'Cash Flow'!$J$14
CF_ReconNpv	'Cash Flow'!$J$13
CF_Row	'Cash Flow'!$D$5
CF_TC	'Cash Flow'!$D$10
CF_WI	'Cash Flow'!$D$12
CF_Wells	'Cash Flow'!$D$11
EC_AdVal	Assumptions!$B$30
EC_DC	Assumptions!$B$33
EC_Dei	Assumptions!$B$13
EC_Disc	Assumptions!$B$40
EC_Dterm	Assumptions!$B$14
EC_Esc	Assumptions!$B$23
EC_FirstOnline	Assumptions!$B$6
EC_GOR	Assumptions!$B$15
EC_Gas	Assumptions!$B$21
EC_GasDiff	Assumptions!$B$22
EC_Gath	Assumptions!$B$36
EC_Hurdle	Assumptions!$B$41
EC_IP	Assumptions!$B$11
EC_LOE	Assumptions!$B$34
EC_LOEVar	Assumptions!$B$35
EC_LifeCap	Assumptions!$B$8
EC_NRI	Assumptions!$B$27
EC_Oil	Assumptions!$B$19
EC_OilDiff	Assumptions!$B$20
EC_PA	Assumptions!$B$37
EC_Pick	Scenarios!$C$2
EC_SevGas	Assumptions!$B$29
EC_SevOil	Assumptions!$B$28
EC_Spacing	Assumptions!$B$7
EC_TC	Assumptions!$B$16
EC_WI	Assumptions!$B$26
EC_Wells	Assumptions!$B$5
EC_b	Assumptions!$B$12

Opens in	Works in any Excel: formulas and named LAMBDAs only, no add-in needed.
File	WellProgramEconomics.xlsx, 35 KB
Category	Economics
For agents and tools	Structure (.json) · Descriptor (.md)

Tags:

economicswell-programscenario-analysisexcel-tablenpvirrpayoutpv-ieurtexasseverance-taxworking-interestarps