Being in UK I work in GBP rather than USD

I have had my miners running properly now for 2 weeks continuous all of them are linked to nicehash, prior to yesterday the average earning was £1 per hour per miner over a 24 hour period ... therefore giving me a return of £24 per miner per day ...

However since yesterday each miner has averaged £0.65 per hour giving a daily return of £15.33 per day ... thats a drop of 35%!!!!! WTF!! ... I am aware that the price of Bitcoin has dropped (choice of payment for nicehash) .. however if you note the amount in BTC rather than the value of the BTC .. you will still note the same pattern:

Prior to yesterday Hourly earned per miner = 0.0003171 BTC = Daily earning = 0.0076104 BTC

current hourly earned per miner = 0.0002518 BTC = Daily earning = 0.0060432 BTC


This is not looking good!!!