Puberty is normally associated with rapid and ungainly growth spurts. But as Aim, the London Stock Exchange’s junior market, enters its 13th year, its expansion looks to be stalling.

In the 12 months to the end of August, Aim saw 365 admissions and 259 cancellations, giving it a net gain of 106 companies – easily the smallest year-on-year percentage rise since its June 1995 foundation.