Year 1	Year 2	Year 3
Assets:
Residence	50,000	50,000	200,000
Stocks and bonds	10,000	10,000	10,000
Automobiles	15,000	15,000	40,000
Cash	5,000	8,000	20,000
Liabilities:
Mortgage balance	40,000	30,000	0
Auto loan	8,000	5,000	0
Student loans	10,000	8,000	0
Income:
Salary	30,000	35,000	40,000
Other	0	1,000	1,000
Expenses:
Mortgage payments	5,000	5,000	0
Car payments	1,000	5,000	2,500
Student loan payments	1,000	1,000	500
Other living expenses	15,000	15,000	20,000
Total living expenses	22,000	26,000	23,000

Calculate the amount of income from unknown sources