5 Pounds Royal Bank of Scotland

The signature progression on this series doubles as a corporate biography nobody ordered. Charles Maiden signed as Managing Director in the opening dates; George Mathewson followed across six dates spanning his tenure as Chief Executive and then Group Chief Executive; Fred Goodwin's name appears on the 2000 and 2005 dates, bracketing RBS's aggressive acquisition phase that would end in the 2008 near-collapse; Stephen Hester's two dates, November 2008 and November 2010, belong entirely to the government-backed rescue period, when RBS was majority state-owned.

De La Rue printed the series throughout, a consistent anchor across two decades of otherwise turbulent institutional history.