There were 63 baptised in Scotland at the convention. Add on those baptised at the circuit & special days and you are maybe talking about 140 for the year. That's in a country of 5.5 million people and is mostly made up of JW kids getting their rite of passage dunk at 14 - 16 years old. So maybe 50 have come in through the ministry. That is a tiny amount and doubtless typical of most european countries. The WTBTS has definitely gone ex-growth now in the 1st world.
There were around 340 (ish) baptised at Twickenham and I recall the number for all the conventions around the UK being somewhere around 700. I know many waited for Twickenham so I expect the numbers at SA/CA events to be less. I still expect growth for the UK at around 1-2%.