My maths failing?

[Silvabod]

Given - interest calculated daily, paid monthly. no interest change in this
timescale.

Quoted rates are Annual rate 5.34% gross = AER 5.45% (less 20% tax from
both rates, = NET)

THOUGHT it would be a relatively simple matter to forward calculate, in
round terms.

Calculated the # of days in each interest period, divided the (NET) interest
by that, to arrive at the average daily interest earned for each period.

Given the capital is only increased by the net interest, I would have
expected this average "daily" interest to be a regular small upward
progression - NOT SO.

Short extract
31 Aug 44889.72
29 Sep (29 days) net interest + 148.46 = 45038.18 (148.46 / 29 = daily
rate 5.11931
31 Oct (32 days) " " + 153.93 = 45192.11 (153.93 / 32 = "
" 4.81031
30 Nov (30 days) " " + 155.50 = 45347.51 (155.50 / 30 = "
" 5.18333
29 Dec (29 days) " " + 163.92 = 45511.53 (163.92 / 29 = "
" 5.65241

Where am I going wrong?

 

[Bill Kuunders]

Nothing much wrong with your calculations.

Maybe you need to check with your bank and find out that the number of days
in each period is right.
They may have a cycle to calculate at each last friday or something silly
like that.
Is the interest compounded monthly?

 

[Silvabod]

Bill, thanks for the moral support!

Nothing much wrong with your calculations.

Maybe you need to check with your bank and find out that the number of
days in each period is right.
They may have a cycle to calculate at each last friday or something silly
like that.
Is the interest compounded monthly?