In December, Hilga sells her German language translation business to Chia-Ching. The sales agreement includes a provision that for an extra $6,000, Hilga will not open another German language translation business in the area for two years. Chia-Ching pays Hilga the $6,000 in January. In June, Hilga opens a European language translation business in a neighboring state and advertises it in Chia-Ching's locality. Has Hilga realized income? If so, when does she realize the income?