Dear list,

I've got a rather complicated problem:
I need to calculate the number of days an animal stays in an age-group,
based on its growth (depends on the weight of the animal and the day of the
year).

The weight of an animal on day x van be calculated as Wx = W(x-1) +
(0.1*W(x-1)^(2/3)-0.05*W(x-1))*f(Temp) With f(Temp) is a temperature
dependent function (ranges from 0-1).

In column A I calculated f(Temp) for each day (365 rows). In column B I want
the number of days before the animal reaches a certain weight (let's say, 10
grams). The number of days depends on the day of the year the animal enters
the simulation (Temp dependence).
A fictive example below:

A B
f(Temp) # days
0.30 30
0.31 29.3
0.32 29
0.33 ...
0.34
....
0.99
1.00
0.99
0.98
....
0.30

So, B2 (and the other cells in column B) should be something like (e.g.
start weight = 1 gram):
countnumberofdays while Wx=W(x-1)+(0.1*W(x-1)^(2/3)-0.05*W(x-1))*f(Temp) <=
10 grams.
I think it should be something with a Do ... Loop function, but I'm a
complete VBA nitwit.

Does anyone knows if this is possible?

Maarten