Learn Farsi: در این نمودار، میانگین حقوق کارگران هشتاد درصد افزایش پیدا کرد. - In this chart, the average salary of the workers increased by eighty percent.

In this sentence, the actual grammatical subject is miyaangin (average), not the workers themselves. Because miyaangin is a singular, inanimate concept, the verb takes the singular form kard. This is a key rule for subject-verb agreement: always look for the core noun of the subject phrase.

Why does hashtood darsad (eighty percent) come right before the verb phrase?

In Farsi, percentages that show how much something changed act as adverbs. Adverbs of degree or quantity are typically placed immediately before the verb they modify. Here, it sits right before afzaayesh peydaa kard to show the exact amount of the increase.

Doesn't peydaa kard usually mean 'found'? Why is it translated as 'increased' here?

You are exactly right that peydaa kardan means 'to find' on its own. However, in Farsi, it is frequently used to build compound verbs. Here it pairs with afzaayesh (increase or growth). The whole phrase afzaayesh peydaa kardan literally translates to 'to find an increase', which is the standard way to say 'to increase'.

How do we link the words for 'average', 'salary', and 'workers' together in Farsi?

They are linked using an Ezafe chain, which is formed by adding a short 'e' sound between nouns. Miyaangin (average) links to hoghoogh (salary/wages), which links to kaargaraan (workers). This creates miyaangin-e hoghoogh-e kaargaraan, literally meaning 'the average of the salary of the workers'.