Shares of TJX Companies are tumbling Tuesday after the owner of discount retail chain T.J. Maxx missed earnings and revenue estimates in its first quarter. The company earned 64 cents a share, which though higher year over year, missed expectations by 3 cents. Meanwhile, revenue of just under $6.5 billion fell short of an expected 7% increase. Also pushing shares lower, management shaved 2 cents off its full-year earnings guidance, now expecting profits between $3.05 and $3.17 a share. That came in lower than analysts' consensus of $3.19 a share. The results compound negativity surrounding the retail sector Tuesday. Staples, Home Depot and Urban Outfitters each reported a weak quarter.