Hello,
I am a student and I shall make a table for calculating a reduce loan plan with factor.
I have a printed plan and should make a table on it..

so..

there is a few columns
number date days principal before payment interests principal payment monthly payment reminder of debt
1 1.5.2014 30 1000 79,97 83,33 163,3 836,7
2 1.6.2014 30 916,67 67,81 83,33 151,14 765,53
3 1.7.2014 30 833,34 61,64 83,33 144,97 688,37
4 1.8.2014 30 750,01 55,48 83,33 138,81 611,2
5 1.9.2014 30 666,68 49,32 83,33 132,65 534,03
6 1.10.2014 30 583,35 43,15 83,33 126,48 456,87
7 1.11.2014 30 500,02 36,99 83,33 120,32 379,7
8 1.12.2014 30 416,69 30,82 83,33 114,15 302,54
9 1.1.2015 30 333,36 24,66 83,33 107,99 225,37
10 1.2.2015 30 250,03 18,5 83,33 101,83 148,2
11 1.3.2015 30 166,7 12,33 83,33 95,66 71,04
12 1.4.2015 30 83,37 6,17 83,37 89,54 0
1486,84

I need a formulas to calculate automatically this example

credit 1000 Euro
12 payments periods
sum of mountly payment = (credit loan) * ≤ factor 1.49

I mean if you take a loan for 1000 Eur maximum return sum should be 1.49 more
in this example take 1000 Eur, return 1486,84.

Help me pls...
Cant find correct formula for factor...

Thanx in advance