Error while running event ab_logisticscenter::on_research_finished (ID 18)
ab_logisticscenter/logistics_center/technology.lua:88: attempt to perform arithmetic on local 'decrement' (a nil value)
stack traceback:
ab_logisticscenter/logistics_center/technology.lua:88: in function 'research_chest_power_consumption'
.../logistics_center/event_handler/on_research_finished.lua:12: in function <.../logistics_center/event_handler/on_research_finished.lua:6>
