In calculating the interest rate for the Tracker product, we use 3 Month GBP LIBOR which we take from Global rates. It is calculated to 2 decimal places and always rounded-up.
We update LIBOR for the Tracker product every quarter (1st January, 1st April, 1st July, 1st October). However, we will use the 15th of the previous month as the reference point. For example, during the period 1st January - 31st March, the effective LIBOR rate will be that from 15th December.