Opinion: #banks compounding annual interest with the arithmetic mean every month means they are fundamentally lying about the annual interest.
Compounding interest is a multiplicative process, and so using an additive average is a sleight-of-hand at best.
They should either use the geometric mean of the annual rate per month or simply give interest in monthly figures and the true annual rate.
Don't know if this counts as an #UnpopularOpinion for #finance peeps, but it shits me to no end.