5%好像應該是年息，假設月息 5%/12
那借用 10000，10年還，每月要還107 (10年付出 12840)

10000 107
9934.220833 107
9868.167587 107
9801.839118 107
9735.234281 107
9668.351924 107
9601.190891 107
9533.750019 107
9466.028144 107
9398.024095 107
9329.736695 107
9261.164765 107
9192.307118 107
9123.162564 107
9053.729908 107
8984.00795 107
8913.995483 107
8843.691297 107
8773.094178 107
8702.202904 107
8631.016249 107
8559.532983 107
8487.751871 107
8415.67167 107
8343.291136 107
8270.609015 107
8197.624053 107
8124.334986 107
8050.740549 107
7976.839468 107
7902.630466 107
7828.112259 107
7753.28356 107
7678.143075 107
7602.689505 107
7526.921544 107
7450.837884 107
7374.437208 107
7297.718197 107
7220.679523 107
7143.319854 107
7065.637853 107
6987.632178 107
6909.301479 107
6830.644401 107
6751.659586 107
6672.345668 107
6592.701275 107
6512.72503 107
6432.415551 107
6351.771449 107
6270.79133 107
6189.473794 107
6107.817435 107
6025.820841 107
5943.482595 107
5860.801272 107
5777.775444 107
5694.403675 107
5610.684524 107
5526.616542 107
5442.198278 107
5357.428271 107
5272.305055 107
5186.82716 107
5100.993106 107
5014.801411 107
4928.250583 107
4841.339127 107
4754.065541 107
4666.428314 107
4578.425932 107
4490.056873 107
4401.31961 107
4312.212608 107
4222.734328 107
4132.883221 107
4042.657734 107
3952.056308 107
3861.077376 107
3769.719365 107
3677.980696 107
3585.859782 107
3493.355031 107
3400.464844 107
3307.187614 107
3213.521729 107
3119.465569 107
3025.017509 107
2930.175915 107
2834.939148 107
2739.305562 107
2643.273501 107
2546.841308 107
2450.007313 107
2352.769844 107
2255.127218 107
2157.077748 107
2058.619739 107
1959.751488 107
1860.471285 107
1760.777416 107
1660.668155 107
1560.141772 107
1459.19653 107
1357.830682 107
1256.042476 107
1153.830153 107
1051.191946 107
948.1260788 107
844.6307708 107
740.7042323 107
636.3446666 107
531.5502694 107
426.3192288 107
320.6497256 107
214.5399328 107
107.9880159 107
0.992132606 107
-106.4495668 107