Table:
| ($ in millions) |  |  |  |
| --- | --- | --- | --- |
| For the year ended December 31: | 2019 | 2018 | Yr.-to-Yr. Percent Change |
| Other (income) and expense |  |  |  |
| Foreign currency transaction losses/(gains) | $(279) | $(427) | (34.6)% |
| (Gains)/losses on derivative instruments | 15 | 434 | (96.6) |
| Interest income | (349) | (264) | 32.2 |
| Net (gains)/losses from securities and investment assets | (32) | (101) | (67.9) |
| Retirement-related costs/(income) | 615 | 1,572 | (60.9) |
| Other | (937) | (63) | NM |
| Total consolidated other (income) and expense | $(968) | $1,152 | NM |
| Non-operating adjustments |  |  |  |
| Amortization of acquired intangible assets | (2) | (2) | 50.0% |
| Acquisition-related charges | 154 | 0 | NM |
| Non-operating retirement related costs/(income) | (615) | (1,572) | (60.9)% |
| Operating (non-GAAP) other (income) and expense | $(1,431) | $(422) | 239.4% |
Paragraphs:
Other (Income) and Expense
NM—Not meaningful
Total consolidated other (income) and expense was income of $968 million in 2019 compared to expense of $1,152 million in 2018. The year-to-year change was primarily driven by: • Lower non-operating retirement-related costs ($957 million). Refer to “Retirement-Related Plans” for additional information. • Higher gains from divestitures ($833 million) reflected in Other; and • Higher net exchange gains (including derivative instruments) ($272 million). The company’s hedging programs help mitigate currency impacts in the Consolidated Income Statement.
Operating (non-GAAP) other (income) and expense was $1,431 million of income in 2019 and increased $1,010 million compared to the prior-year period. The year-to-year change was primarily driven by the same factors excluding lower non-operating retirement-related costs.
Question:
What caused the Operating (non-GAAP) other (income) and expense to increase?
Answer: The year-to-year change was primarily driven by the same factors excluding lower non-operating retirement-related costs.