Book-keeping hourly rates

Having specialised in book-keeping for 5-10 person companies for many years that part of my world is coming severely apart. I have quoted for several companies in the past 6 months but none have taken up the quote. More disturbingly, companies I have dealt with for 20 years or more are departing, many taking the work in-house. I can only assume that my current hourly rate of £43 is deemed far too high and the fact that I am 4 times as fast as the average book-keeper, and the benefit of using me is that tax fees are vastly reduced is not felt to be an issue any more.

New tax prospects are going to resist the present hourly rate quite clearly. One already has, but I didn't read the situation properly to recover it.

What hourly rate is reasonable for a very small company, bearing in mind the competition. £25?