Usage patterns
〈人〉の所得が増える/減るsomeone's income increases/decreases
His income increased compared to last year.
所得に応じて〈物〉が変わるsomething changes according to one's income
Taxes change depending on one's income.
〈人〉が所得を申告するsomeone declares/reports their income
Self-employed people must report their income every year.
所得が〈形容詞〉one's income is (high/low, etc.)
Many people in this area have high incomes.