[carapace]

I didn't have a spreadsheet handy:

    from math import exp

    k = .01
    q = .2
    C = 1
    T = 0
    E = lambda T: 0.1 * exp(-0.01 * T)

    for step in range(3000):
        r = C * E(T)
        m = C * k
        C += r * q - m
        T += r
        print('%5i %g' % (step, C))