On July $1,20$X$3,$ Green Co$.$ invested $$50,000$ in corporate bonds that mature in $5$ years $(60$ months$)$ and that pay interest at an annual rate of $4\%,$ with interest paid semi$-$annually on July $1$ and January $1$ each year over the life of the bonds. At maturity, Green Co$.$ will have the $$50,000$ principal returned. How much interest income did Green Co$.$ earn during its fiscal year ended December $31,20$X$3?$