Stocks were lower for their second day in a row in nervous trading ahead of a loaded back-half of the week. Thursday will be busy with U.K. citizens heading to the polls, the ECB making a policy decision, and fired FBI Director Comey delivering public testimony. The U.S. labor market ended April with just over six million job openings, a record high and far higher than analysts expected, according to the JOLTs survey. However, hiring slowed indicating employers were having a tough time filling open positions. Michaels  (MIK - Get Report) declined after falling short of profit estimates over its first quarter and guiding for a surprise decline in sales over its second. The crafts retailer anticipates Q2 earnings no higher than 17 cents, two cents below consensus. Francesca's  (FRAN - Get Report)  slumped after falling short of estimates on its top- and bottom-line over its recent quarter. Same-store sales fell by 5%, ten times the expected drop.