Could you increase a yield by x per era?

[VainApocalypse]

Say you are using a modifier on the civilization's UA to give some yield.

--------------------------------------------------------------------------------------------------------------------------
-- ModifierArguments
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INSERT INTO ModifierArguments
        (ModifierId,                                                Name,                        Value)
VALUES    ('VN_TRAIT_TRADE_CULTURE',                          'YieldType',                    'YIELD_CULTURE'),
        ('VN_TRAIT_TRADE_CULTURE',                              'Amount',                       '2'),

How would you make it so that the yield increases by 2 each era (ancient = 2, classical = 4, medieval = 6, etc.)?

 

[Aldollin]

there are requirementtypes you can use to make a modifier be only active if the players era is at least some specified era,
so what you could do is create on modifier for each era that increases culture by 2
i did pretty much that for a unique building, and i works just fine