By Rupert Hargreaves Weatherbys, the private bank founded in 1770, reported a jump in profit before tax as the lender benefited from higher interest rates and growth into new markets. In itsannual report, published on Thursday, the company said profit before tax rose from £15.2m in 2022 to £33.1m for 2023. The lender’s return on equity rose 34.2 per cent, while its net interest margin—the difference between the rate of interest paid out to depositors and the rate charged to borrowers—rose to 4.82 per cent. Weatherbys Group is comprised of Weatherbys Private Bank, Weatherbys Racing Bank, Arkle …