Ashtead's first quarter numbers have confirmed the bullish trend seen in the results of its US competitors, according to Singer Capital Markets, which has reiterated its buy rating on the plant hire group.The firm - which rent lifts, generators, diggers and pumps - reported a 21% increase in revenue (at constant currency) to £268.6m, while EBITDA (earnings before interest, tax, depreciation and amortisation) rose by 29% to £93.9m.Given the "very, very good results", as Singer calls them, Ashtead now expects full-year results to be "substantially ahead of its previous expectations."By 11:57, shares were 19.20% ahead at 133.50p."We remain comfortable with our top of the range forecasts and buy recommendation, although we anticipate the consensus could rise to at least our top of the range level," said analyst Andy Murphy.Singer's target price stays at 222p.BC