Excuse my inquisitiveness. According to my professors and from hearsays, Philippines is a country rich in resources, so rich that if it were to trade its resources we would be able to pay our debt of rougly 6 trillion five or ten times. Flashback to 16th-18th century, I remember being taught we exported Manila Hemp and by-products of the Indigo plant to wealthy western countries. A lot of indios also planted cash crops for income. However, our professors only present/tell us students statistics and I have difficulty believing statistics. So I need more proof from other literature suggesting that Philippines was a rich country during 16th-19th century.
A reply to /u/lady65432
Within my 16th-17th century focus, I'm not sure about "Philippines was very rich in resources", but it was a very important entrepot for the Spanish global empire, as it gives them access to the "Indies". I wrote a bit about this here. Portugal and Spain had treaties restricting their areas of operation and exploration, so Spain's access to Asia had to go through the Americas, and then through the Manila Galleons across the Pacific.
Many have heard of the infamous silver mines of Peru and Mexico. But fewer know that most of the silver from Mexico, which rose to become the largest producer of silver by the 1660s, went to the Philippines, taken by the famous Manila Galleons.
At the Philippines, they were traded for even more valuable goods, such as silk and porcelain from Chinese traders, spice and sandalwood from Indonesia. They were then shipped back across the Pacific to New Spain Mexico, then finally to the Casa de Contratacion in Seville.
Locally in China, the volume was such that farmers in fertile regions such as Jiangnan substituted rice for silk. The total import of silver in this period was around 600 metric tons.
In the 16th-17th centuries, Spain had very little presence in the Philippines, restricted mostly to Manila. European powers largely maintained trading posts and tried to control maritime trade. It was not yet the period where there were large scale plantations of valuable commodities, that's mostly a 19th-20th phenomena, similar to what happened in the Dutch East Indies and India.
Your professor should be much more specific about what revenue, from what activity, in which period.