Why does Jakarta have such small market sizes in the 1960s? In later games it is a large airport. In Jet Age it seems like no domestic market from Jakarta's airports is more than 40 pax per day
While I have no idea about Indonesian aviation, especially in the earlier decades, I do know that in AWS the two airports Jakarta has until the new airport opens (which I believe is 1985) lack demand practically everywhere, with the exception internationally to HKG from Halim Perdanakusuma Airport. When the new airport opens, for example, where will be around 3,000PAX daily to Singapore (from about a sixth of that from the old airports combined), and most domestic routes will see a large spike in demand. Kemayoran Airport has no significant demand anywhere, but I'm not sure if that modeled reality or if it is undervalued.