IBM reported second-quarter sales declines across all of its major business units, marking the 13th straight period of falling revenue. Profit excluding some items was $3.84 a share, IBM said in a statement Monday, as reduced administrative and research costs offset declines in its services and software businesses.

"Our results for the first half of 2015 demonstrate that we continue to transform our business to higher value and return value to shareholders. We expanded margins, continued to innovate across our portfolio and delivered strong growth in our strategic imperatives of cloud, analytics and engagement, which are becoming a significant part of our business," said Ginni Rometty, IBM chairman, president and chief executive officer.

IBM expects full-year 2015 GAAP diluted earnings per share of $14.25 to $15.00, and operating (non-GAAP) diluted earnings per share of $15.75 to $16.50. IBM now expects a modest increase in free cash flow, improved from its prior expectation of flat year-to-year performance.