Peel Hunt has upgraded its rating for international publishing and events group Euromoney Institutional Investor from hold to buy and maintained its target price at 800p.Revenue guidance was given at the pre-close update, meaning that top-line figures were broadly in line. However, profitability exceeded expectations."Though results were in line and guidance on trading not significantly changed, we are upgrading by 6% this year at the EPS [earnings per share] line as the company enjoys a one-off credit at the CAP cost line and a 4% improvement on proposed tax rate," said analyst Malcolm Morgan.Notably, the tax rate guidance reduced from 27% to 23%.With the shares having drifted back towards to the 700p level recently, the broker moves back to a buy.Just before midday on Tuesday, shares were trading 1.75% higher at 727.5p.BC