Small-cap stocks struggle amidst banking woes and tech success.

The small-cap Russell 2000 is down about 1% this year, compared to a rally that has boosted the S&P 500, an index representing the largest U.S. companies, 7% year-to-date. The weakness in shares of smaller companies is one of several signs that investors are uneasy about the economic outlook. Small caps have tended to waver ahead of economic weakness in the past. Since 1980, the Russell 2000 has lagged the S&P 500 by an average of about four percentage points in the six months after the economic cycle has peaked, ahead of a recession, according to Strategas data.