Using the EV insides numbers, as of end of september, GM has sold 146,665 Volt/Bolt/Sparks since 2010
The current sales rate of Volt/Bolt is ~3500 month
So if things stay the same sales rate ( which would be all time yearly sales rate by a long shot ), and you have the 3-6 month grace period once 200K is met, it will be 1st or 2nd quarter 2019 at the earliest, before the reductions start on the tax credit get reduced, probably into 2020 as Volts will be end of life by them so yearly total will likely drop
The current sales rate of Volt/Bolt is ~3500 month
So if things stay the same sales rate ( which would be all time yearly sales rate by a long shot ), and you have the 3-6 month grace period once 200K is met, it will be 1st or 2nd quarter 2019 at the earliest, before the reductions start on the tax credit get reduced, probably into 2020 as Volts will be end of life by them so yearly total will likely drop
