There are few certainties in politics but sterling's exchange rate has followed a fairly consistent trend in recent decades, regardless of which party formed the government.

Everyone else can only wonder at the largesse being extended to an already fortunate group - which has been the most consistent trend in the mortgage market for a while.

Since 1991, the rate has shown no consistent trend and has fluctuated between 84.8% and 86.5%.

From annual counts between 1980 and 1996, variable estimates of population ranged from 1,584 to 5,685 mature birds, though there are no consistent trends.