A risk manager is evaluating the price sensitivity of an investment-grade callable bond. The data collected on the bond and its embedded call option are shown in the table below:

Interest Rate Level	Callable Bond Price	Call Option Price
3.95%	97.9430	2.1972
4.00%	97.8910	2.1090
4.05%	97.8566	2.0035

Assuming that the current interest rate curve is flat at 4%, calculate the approximate effective convexity of the callable bond.