I do not understand why 2.2 is not the correct answer. I am calaculating 130 as total assets, 117 as total liabilities and then plugging into the formula for duration gap so 4-2(117/130)=2.2. Not sure where my mistake is, please help!

The following entries (in millions of dollars) are from the balance sheet of Rivendell National Bank (RNB): $25 $50 $27 $6 $46 $10 U.S. Treasury bills Demand deposits Mortgage-backed securities Loans from other banks C&l loans Discount loans NOW accounts Savings accounts Reserve deposits with Federal Reserve Cash items in the process of collection Municipal bonds Bank building $39 $12 $10 $10 $4 If RNB's assets have an average duration of four years and its liabilities have an average duration of two years, what is RNB's duration gap? Duration gap = 2.2 The following entries (in millions of dollars) are from the balance sheet of Rivendell National Bank (RNB): $25 $50 $27 $6 $46 $10 U.S. Treasury bills Demand deposits Mortgage-backed securities Loans from other banks C&l loans Discount loans NOW accounts Savings accounts Reserve deposits with Federal Reserve Cash items in the process of collection Municipal bonds Bank building $39 $12 $10 $10 $4 If RNB's assets have an average duration of four years and its liabilities have an average duration of two years, what is RNB's duration gap? Duration gap = 2.2