Your pension is linked to the RPI - not base rates. The connection is that if the RPI increases, the BoE will raise interest rates, and vice versa.
It is important to note that your pension is linked to the RPI and not the CPI. The RPI has been calculated for many years now. The CPI was dreamt up by this Chancellor to exclude all those goods and services he wanted to tax. The BBC has duly fallen in line with the pressure and only quotes the CPI. The RPI is currently running at a much higher rate than the CPI.
RPI = Retail Price Index
CPI = Consumer Price Index
BBC = Brown's Broadcasting Corporation