A bond with a face value of $1,000 was issued at par (sold for its face value) 5 years ago when market interest rates were 3.0% p.a. (compounded annually). It now has exactly 3 years remaining until it matures. If it pays coupon interest annually, and current market rates are 2.2% p.a. (B.E.Y. convention - all maturities), calculate the duration of the bond.