But I bet you haven’t lost 15%.
Mrs MB is a band 6 nurse. Inflation linked top of her band should be £43,078 and it is actually £37,890. So it looks like she is being underpaid by 13% (which I guess is where you are coming from), however she is also getting an extra £6,025 in tax free allowance since 2010 so she is actually about £900 better off than she was in 2010.
Band 5s are £2k better off, 4s nearly £3k better off, 3s nearly £4K better off. And that’s ignoring that you would have been paying MORE tax on those earnings so in actual fact you are taking home even more money than these numbers suggest.
Things aren’t always as they seem. You still deserve a decent pay rise though.