The UK is on track to lose more millionaires this year than any other country in the world, according to a new global wealth migration report that underscores growing concerns over the nation’s economic competitiveness and high-tax environment. Henley & Partners, a specialist advisory firm, forecasts that 16,500 millionaires will leave Britain in 2025, more than double the 7,800 expected to exit China — which had previously topped the list for 10 consecutive years. The...