As posted by explorer- Canadian economy is heavily reliant on U.S economy (because of their trade links)..A couple of weeks back, when S&P downgraded U.S ratings, USD fell against all currencies except CAD..(CAD likewise tanked versus other currencies)...
As posted by Omsai- the price is highly dynamic and is decided by a 24 hour spot forex market (it has a $4 trillion/day turnover-participants vary from central banks,big companies to retail traders)...Again as Omsai pointed out, the biggest gainer a week back was swiss franc (usd/chf)- which typically is considered a safe haven for investments along with gold during turmoil.
This week, the swiss national bank (SNB) stated that they will aggressively intervene in the forex market to prevent their currency to appreciate further (thereby protecting their exporters whose margins were taking a hit)...Since then Swiss Franc has fallen by more than 8%.
This is how currency markets fluctuate (If this is the fluctuation in a couple of weeks, you can imagine the variation over 2 months, which is the time period that you have indicated).
As you have mentioned that you are concerned with CAD falling v/s GBP , adversely impacting your business margin (I am assuming that you are an importer/exporter), I would suggest that you talk to a bank/specialist to help you hedge your currency risk (using either currency futures /spot forex or options)...
Regards