JPMorgan Chase & Co. posted fourth-quarter profit ahead of market expectations on Friday, but its shares fell as much as 6 percent as analysts expressed disappointment over its forecasts for future profitability. The country’s largest bank warned that its return on tangible capital equity (ROTCE), a key metric which measures how well a bank uses shareholder money to produce profit, may fall below its medium-term target of 17 percent this year. A slowdown in capital markets activity, the cost of investing in the business, including new technology and branch openings, and rising expenses due in part to higher inflation and labor costs, were some of the factors the bank cited as headwinds in the coming year. However, it retained a medium-term target for 17 percent ROTCE beyond 2022, saying it expected to benefit from rising interest rates and the longer-term growth of businesses resulting from its investments. That guidance disappointed …