在实施西部大开发战略的过 程中，农业的基础作用在西部地区表现得更为突出，农业的机械化程度也越发显得重要。那么，西部农机企业每年生产的各种拖拉机产量有多少？占全国总产量的比重有多少呢？资料显示，１９９９年的情况如下： 从小拖产量来看，四川、新疆、云南、甘肃、 In the process of implementing the strategy for the large-scale development of the western region, the basic role of agriculture has become more prominent in the western region, and the degree of mechanization of agriculture has become increasingly important. Then, what is the output of various tractors produced by western agricultural machinery enterprises each year? What is the proportion of the total output of the country? According to statistics, the situation in 1999 was as follows: From the perspective of small output, Sichuan, Xinjiang, Yunnan, Gansu,