Proportional multiplication

Hello,
Dear All

my model has 100 healthy people moving over 100 cycle with constant weight of 5. Once a person gets infected, he(she) loses weight at a rate of 0.0168 at each cycle. the probability of a person moving from healthy state to infected state per cycle is 0.108.

My problem is each cycle a proportion moves from healthy to infected e.g:


cycle healthy infected total weight
0 100 0 5*100
1 100-(100*(0.108)) 100*0.108 5(100-(100*(0.108))+((5-0.0168)*0.108)The people in the cycle 2 moving from health to infected have a drop of 0.0168 while people already in infected state have a drop of 2*0.0168.

How to write a macros for this..

since the weight is constant for healthy and drops at a constant rate once a person is infected, the proportiona of people drpooing from 56 will differ each cycle i.e. each cycle fresh no. of patients will come to infected state, thier weight will drop from 56 while the weight of the already infected will drop from the previos rate



fresh infected: weight change is 56 -0.0168
while alreasdy infected will be 56 - (2* 0.0168) so the total weight will be thealthy *weight by infected _cycle1(2*0.0168+infectedcycle2(0.0168)
PLEASE need help.