各位老师好，这是在网上搜到的“2021年6月CATTI二级笔译真题”中的一段Worldwide, the share of national income going to labour (rather than to other factors of production) declined substantially between 2004 and 2017, from 54 percent to 51 percent.

请问going to labour在句中的成分是后置定语吗？为什么要用动词的ing形式？