BOSTON ( TheStreet) -- Small-cap stocks soared to a record last week even as the economy struggles to find its footing, leaving investors to wonder how to adjust their portfolios as volatility ramps up before the summer doldrums take hold.Mutual fund managers are telling clients to stick with large-cap stocks because they offer greater value. The Russell 2000, considered the best benchmark of small-cap stocks, jumped to an all-time high last Monday, topping its previous record set in 2007. Since the low set in March 2009, the small-cap index is up more than 140%, outpacing a gain of less than 100% on the broader S&P 500 index. However, the Russell 2000 declined for the rest of the week as investors sold risk-laden stocks and commodities. Many investors are wondering if small-cap stocks have completed their run.