Neutral Army Growth

Neutral monster armies in Heroes IV grow over time. I did some experiments to figure out the growth rate.

Data

turn 50 peasants 100 1000
1 50 100 1000
2 50 101 1005
3 51 102 1010
4 52 104 1015
5 52 105 1020
6 53 107 1025
7 54 108 1030
8 55 110 1035
9 55 111 1041
10 56 113 1046
11 57 115 1051
12 58 116 1056
13 59 118 1061
14 60 120 1066
15 60 121 1071
16 61 123 1077
17 62 125 1082
18 63 127 1087
19 64 128 1092
20 65 130 1097
21 66 132 1102
22 67 134 1107
23 68 136 1113
24 69 138 1118
25 70 140 1123
turn 50 catapults 100 1000
1 50 100 1000
2 50 100 1000
3 50 100 1000
4 51 101 1001
5 51 101 1001
6 52 102 1002
7 52 102 1002
8 52 102 1002
9 53 103 1003
10 53 103 1003

Hypothesis

The growth rate seems to be about 1.4% per day, rounded to the nearest whole number of creatures. That is, given an initial number of creatures C_i, the number of creatures C in the army on day D is given by the formula

C = round(C_i * 1.014 ^ (D - 1))

However, there seems to be a cap on the growth rate. For peasants, it is about 5.125 creatures per day. For catapults, it seems to be around 1/3 of a creature per day. I don't know how the cap is determined.

Hypothesis: the growth rate cap is 5.125 * sqrt(S) PEONS per day, where S is the strength of an individual creature in PEONs. Note that catapults have an individual strength of 200 PEONs.