How do you figure compounded interest and diff in interest rates with penalty included.?

We traded in cd's because of a 1.34% increase in rates. The old includes a 180 day penalty but new interest goes out 15 months now. how to figure my net gain?How do you figure compounded interest and diff in interest rates with penalty included.?
It won't exact but you could probably just go off simple interest to get a *very* rough idea. I'm not familiar with the exact terms of the penalty, but if you mean a 180-day penalty on interest, that's pretty severe.





If you have 1000$, and it's earning 3%, you would have gotten 45$ over 15 months.





Earning 4.34% with a 180-day penalty is (65.1 - 15) = 50.1





The numbers would both be slightly higher for the daily compounding. It's also not exact if the first was only a 12 month because then you would have had to roll over the money into a new account anyway and the margin would be less as interest rates have clearly been going up.How do you figure compounded interest and diff in interest rates with penalty included.?
Sorry, I am not clear about what you mean.