At the same time, the land frontier was closing and it became harder to add new land. Consequently, agricultural growth slowed to about 2%-3% per year, although productivity increased notably. Given opportunities in both domestic and international markets, new activities emerged such as rubber, cassava, pineapples, and high value perishables for the fast-growing cities. Most farm households have diversified their income sources, while some have become more specialised in higher-value agricultural products sold into more sophisticated marketing chains. The rural non-farm economy has grown to the point where it provides around half of all rural jobs.