Massive fps drop when lights are on

I made an apartment with total of 5 light sources. When the lights are off it’s all fine (around 110 fps). When I turn them on the fps drops to 20.

I am using point lights as light sources with following settings:
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Is there anything I could do with the lights (or some other settings) to reduce this effect? Their range is greater than the room they are supposed to illuminate.

Lightmapping static objects is the best way to go about this.