Choppy waters for Seagate Technology

Tech troubles: Seagate Technology shares dropped 17 percent to $28.09 Thursday after the electronic storage maker said third-quarter profit margins and revenue will be lower than expected. The company said it's seeing lower demand for some kinds of hard disk drives. Its stock closed the week at $25.59.

Traffic jam: Hertz Global Holdings dropped 11 percent, to $8.69 Monday after the rental car company cut its full-year earnings forecast. The company said the car rental industry is suffering from too much capacity and competition. Hertz shares closed at $8.70 Friday.

Earnings hit: Alcoa, the aluminum mining giant, dropped 3 percent Tuesday to $9.48 after it reported a 15 percent decline in revenue late Monday. Alcoa also had a huge drop in first-quarter profit from a year earlier as aluminum prices fell. Alcoa's stock closed the week at $10.01.

Take it to the bank: JPMorgan Chase shares rose 3 percent to $61.19 Wednesday after it reported a first-quarter profit decline that was less than expected. Overall revenue also exceeded expectations despite weak results in its investment banking business. Shares closed the week at $61.87.

Loss upside: Agriculture and construction equipment company Titan Machinery shares rose 6 percent to $12.15 Wednesday after it said it took a smaller loss than investors expected. Titan stock closed Friday at $12.02.

Flying high: Delta Air Lines' stock rose nearly 3 percent to $49.80 Thursday after it said first-quarter profit jumped 27 percent, helped by low fuel costs. Delta shares closed Friday at $47.50.