醉别西楼醒不记,春梦秋云,聚散真容易。斜月半窗还少睡,画屏闲展吴山翠。半壁见海日,空中闻天鸡。If productivity measures the efficiency of an economy, a measure of what an economic system produces is its gross national product (GNP), which is the current market value of all final goods and services that a nation produces within a particular period. |