The financial data for this case was collected during a fraud investigation:

Case $8$

$$Year $1$Year $2$Year $3$Assets:$$Residence$$280,000$$$280,000$$$280,000$Automobile$18,00045,00045,000$CD$5,00015,00015,000$Cash$8,0008,0002,000$Stock portfolio$3,50015,00015,000$Boat$15,00015,000$Liabilities:$$Mortgage$200,000180,000100,000$Auto loan$12,00030,000$Other loan$18,000$Income:$$Salary$55,00090,000130,000$Investment$800800800$Expenses:$$Mortgage expense$18,00018,00018,000$Auto expense$5,0009,0009,000$Living expenses$20,00020,00020,000$

Without calculating the amount of unknown income, indicate possible red flags or trends you notice in the numbers above.

Now calculate the amount of total income and unknown income using the numbers given. Does it appear that a possible fraud exists? Could there be other explanations for the unknown income?