Microsoft Corp. said on Thursday it will slash up to 18,000 jobs, or 14% of its workforce, this year as it trims its newly acquired Nokia phone business and reshapes itself into a cloud-computing and mobile-friendly software company. The deepest job cuts in the company’s 39-year history come five months into the tenure of Chief Executive Officer Satya Nadella, who outlined plans for a “leaner” business in a public memo to employees last week. About 12,500 of the layoffs will come from eliminating overlaps with the Nokia unit, which Microsoft acquired in April for $7.2 billion. Microsoft did not say how many jobs would come from Nokia and how many from existing operations. The acquisition of Nokia’s handset business in April added 25,000 people to Microsoft, pushing its overall headcount up to 127,000.