A few days ago I read an interview with Hassan Merican about the performance of Petronas of which he is CEO.

It was mentioned that Petronas has assets of about RM270 billion. As far as I know, Petronas also has debts amounting to RM100 billion.

If it has net assets of RM170 billion, does this represent a fair return on Petronas income over its lifespan? Does this total include investment income from profits derived from its early years and now invested?

There should be a breakdown of how much profits Petronas made from investments and operational profits every year. When that happens, then we can measure Petronas' performance in a more meaningful manner.