# Compound interest calculation with varying interest rates

Question asked by bjspeek on Sep 12, 2018
Latest reply on Sep 17, 2018 by fmpdude

Hey,

I have a problem that I can not resolve. I want to calculate compound interest with varying interest rates.

Example:

Amount:          € 1000.00

Start date:       01-02-2009

End date:        30-12-2017

Interest rates

Date of introduction      Percentage

01-07-2016                     8.00%

01-01-2015                     8.05%

01-07-2014                     8.15%

01-01-2014                     8.25%

01-07-2013                     8.50%

01-01-2013                     7.75%

01-01-2012                     8.00%

01-07-2011                     8.25%

01-07-2009                     8.00%

01-01-2009                     9.50%

The calculation should be:

Period                                               Days           Amount           %            Interest

1      01-02-2009 to 01-07-2009      150/365      € 1,000.00      9.50%      € 39.04

2      01-07-2009 to 01-01-2010      184/365      € 1,000.00      8.00%      € 40.33

3      01-01-2010 to 01-02-2010       31/365       € 1,000.00      8.00%      € 6.79

4      01-02-2010 to 01-02-2011      1 year         € 1,086.16      8.00%      € 86.89

5      01-02-2011 to 01-07-2011      150/365      € 1,173.06      8.00%      € 38.57

6      01-07-2011 to 01-01-2012      184/365      € 1,173.06      8.25%      € 48.79

7      01-01-2012 to 01-02-2012      31/366        € 1,173.06      8.00%      € 7.95

8      01-02-2012 to 01-07-2012      151/366      € 1,268.36      8.00%      € 41.86

9      01-07-2012 to 01-01-2013      184/366      € 1,268.36      8.00%      € 51.01

10    01-01-2013 to 01-02-2013      31/365        € 1,268.36      7.75%      € 8.35

11    01-02-2013 to 01-07-2013      150/365      € 1,369.58      7.75%      € 43.62

12    01-07-2013 to 01-01-2014      184/365      € 1,369.58      8.50%      € 58.69

13    01-01-2014 to 01-02-2014      31/365        € 1,369.58      8.25%      € 9.60

14    01-02-2014 to 01-07-2014      150/365      € 1,481.48      8.25%      € 50.23

15    01-07-2014 to 01-01-2015      184/365      € 1,481.48      8.15%      € 60.87

16    01-01-2015 to 01-02-2015      31/365        € 1,481.48      8.05%      € 10.13

17    01-02-2015 to 01-01-2016      334/365      € 1,602.71      8.05%      € 118.06

18    01-01-2016 to 01-02-2016      31/366        € 1,602.71      8.05%      € 10.93

19    01-02-2016 to 01-07-2016      151/366      € 1,731.70      8.05%      € 57.51

20    01-07-2016 to 01-01-2017      184/366      € 1,731.70      8.00%      € 69.65

21    01-01-2017 to 01-02-2017      31/365        € 1,731.70      8.00%      € 11.77

22    01-02-2017 to 30-12-2017      332/365      € 1,870.62      8.00%      € 136.12

Totals                                                                  € 2,006.74                       € 1,006.74

Does anyone have any idea?