Treasury Bond Lab

Personal Finance System · Rwanda

Designed and built by Gabo

TreasuryBonds.

A personal planning system for building long-term RWF income through government bonds, monthly discipline, and transparent coupon tracking.

Adjust my plan View yearly projection

Current scenario · Live model

Invest RWF 300,000 each month for 20 years

Starting July 2026, at a 11.5% annual coupon rate with 100% of net coupons reinvested and 67% expected auction fill. Uninvested cash is held at 0% return.

You contribute

RWF 74.6M

Including extra cash

Projected value

RWF 262.4M

RWF 260.6M in bonds + RWF 1.8M in Cash by June 2046

Potential annual income

RWF 30.4M

Potential monthly income

RWF 2.5M

Assumptions

Tune the model

Monthly contribution schedule

Default is one amount for the full horizon. Add periods for salary changes, pauses, or temporary boosts.

AmountFromUntil

Base · 240 mo.

Current month: RWF 300,000Total periods: 1Every month has a scheduled contribution

Investment horizon20 years

Fallback annual coupon rate11.5% p.a.BK Capital range: 10.65%-13.5%.

Extra cash

One-time injections

0 added

Cash balance already waitingRWF 100,000Cash after draftRWF 400,000

Growth curve

Monthly portfolio steps

Portfolio Contributions

Estimate: 1 USD ~= RWF 1,475, 1 EUR ~= RWF 1,710, then RWF weakens 4.5%/year.

Total cash invested

RWF 74,640,000

Monthly plan, charges, and one-time injections

Modeled bond purchases

240

Each monthly pooled purchase is tracked as one lot

Net coupons earned

RWF 190,425,553

10.9% net annual rate

Coupons reinvested

RWF 190,425,553

100% reinvested

Growth above contributions

RWF 187,785,553

RWF 50MJanuary 2035 · Month 103

RWF 100MApril 2039 · Month 154

RWF 200MMay 2044 · Month 215

Projection

Annual view

Passive income exceeds current annual contributions in Year 7

Year	Invested this year	Extra deposits	Income this year	Account value	Annual passive income
Year 1July 2026 - June 2027	RWF 3,732,000	RWF 0	RWF 91,438	RWF 3,691,438RWF 3,400,000 bonds · RWF 291,438 Cash	RWF 395,913
Year 2July 2027 - June 2028	RWF 3,732,000	RWF 0	RWF 510,198	RWF 7,801,635RWF 7,600,000 bonds · RWF 201,635 Cash	RWF 883,500
Year 3July 2028 - June 2029	RWF 3,732,000	RWF 0	RWF 1,009,613	RWF 12,411,248RWF 12,200,000 bonds · RWF 211,248 Cash	RWF 1,419,775
Year 4July 2029 - June 2030	RWF 3,732,000	RWF 0	RWF 1,556,575	RWF 17,567,823RWF 17,200,000 bonds · RWF 367,823 Cash	RWF 2,001,080
Year 5July 2030 - June 2031	RWF 3,732,000	RWF 0	RWF 2,160,918	RWF 23,328,740RWF 23,000,000 bonds · RWF 328,740 Cash	RWF 2,675,818
Year 6July 2031 - June 2032	RWF 3,732,000	RWF 0	RWF 2,853,183	RWF 29,781,923RWF 29,400,000 bonds · RWF 381,923 Cash	RWF 3,420,665
Year 7July 2032 - June 2033	RWF 3,732,000	RWF 0	RWF 3,620,640	RWF 37,002,563RWF 36,600,000 bonds · RWF 402,563 Cash	RWF 4,258,090
Year 8July 2033 - June 2034	RWF 3,732,000	RWF 0	RWF 4,475,878	RWF 45,078,440RWF 44,500,000 bonds · RWF 578,440 Cash	RWF 5,179,970
Year 9July 2034 - June 2035	RWF 3,732,000	RWF 0	RWF 5,432,433	RWF 54,110,873RWF 53,500,000 bonds · RWF 610,873 Cash	RWF 6,231,145
Year 10July 2035 - June 2036	RWF 3,732,000	RWF 0	RWF 6,511,348	RWF 64,222,220RWF 63,600,000 bonds · RWF 622,220 Cash	RWF 7,408,813
Year 11July 2036 - June 2037	RWF 3,732,000	RWF 0	RWF 7,718,750	RWF 75,540,970RWF 74,800,000 bonds · RWF 740,970 Cash	RWF 8,719,005
Year 12July 2037 - June 2038	RWF 3,732,000	RWF 0	RWF 9,069,270	RWF 88,210,240RWF 87,400,000 bonds · RWF 810,240 Cash	RWF 10,193,310
Year 13July 2038 - June 2039	RWF 3,732,000	RWF 0	RWF 10,583,665	RWF 102,393,905RWF 101,500,000 bonds · RWF 893,905 Cash	RWF 11,841,750
Year 14July 2039 - June 2040	RWF 3,732,000	RWF 0	RWF 12,278,228	RWF 118,272,133RWF 117,300,000 bonds · RWF 972,133 Cash	RWF 13,689,548
Year 15July 2040 - June 2041	RWF 3,732,000	RWF 0	RWF 14,173,288	RWF 136,045,420RWF 135,000,000 bonds · RWF 1,045,420 Cash	RWF 15,764,158
Year 16July 2041 - June 2042	RWF 3,732,000	RWF 0	RWF 16,305,895	RWF 155,951,315RWF 154,700,000 bonds · RWF 1,251,315 Cash	RWF 18,073,608
Year 17July 2042 - June 2043	RWF 3,732,000	RWF 0	RWF 18,684,220	RWF 178,235,535RWF 176,900,000 bonds · RWF 1,335,535 Cash	RWF 20,674,233
Year 18July 2043 - June 2044	RWF 3,732,000	RWF 0	RWF 21,353,910	RWF 203,189,445RWF 201,700,000 bonds · RWF 1,489,445 Cash	RWF 23,581,185
Year 19July 2044 - June 2045	RWF 3,732,000	RWF 0	RWF 24,342,088	RWF 231,131,533RWF 229,500,000 bonds · RWF 1,631,533 Cash	RWF 26,840,445
Year 20July 2045 - June 2046	RWF 3,732,000	RWF 0	RWF 27,694,020	RWF 262,425,553RWF 260,600,000 bonds · RWF 1,825,553 Cash	RWF 30,488,350

Model guide

Useful, transparent, intentionally conservative.

This planner models monthly contributions, partial Treasury bond auction allocation, and uninvested cash at 0% return.

Market price risk

Bond prices can fluctuate if sold before maturity.

Holding to maturity

Holding to maturity avoids market-price loss if the issuer pays as agreed.

Coupon and tenor

BK Capital states tenors of 3, 5, 7, 10, 15, 20, 25 years and annual coupon rates from 10.65% to 13.5%, depending on the issuance.

Auction fill risk

The model defaults to 67% allocation based on the BNR historical sold/applied pattern, not 100% allocation.

Uninvested cash

Unfilled bond money stays as cash at 0% return until it is used for another bid.

Secondary market

Buying or selling before maturity carries a 0.049% commission on turnover on each side.