increase and [or] decrease;〔変化する〕vary, fluctuate
- 人員の増減
- fluctuations [change(s)] in the number of personnel
- 売り上げは月によって増減がある
- Our sales vary from month to month./Our sales fluctuate each month.
- 大都市の人口は増減が少ない
- The population of large cities does not change [increase or decrease] very much.
- 体重の増減
- variation in one's weight/gains and losses in weight