That's a little bit odd. Here in South Africa, you regularly get 'savings'-type accounts that yield 5+ percent interest, guaranteed by the bank. If it weren't for exchange controls, you'd probably have access to the sort of market (like South Africa) that would let you have that kind of interest rate.
Then again, we also have mortgage-loans that are at 10% interest.
There's no free lunch, that high interest rate has to be considered against the currency risk from the weak and unstable ZAR. In the last 5 years a 5% interest rate will have compounded to a 27% one. In the same time the ZAR has weakened against the USD by 125%.
You will not find a combination of a stable currency and high guaranteed interest rates anywhere.
Then again, we also have mortgage-loans that are at 10% interest.