Counting annual high mileage

i am planning on ridding 5,000 miles in 2020. Knowing the weather can take me to La Fitness ,spending an hour or more on a spin bike a few days a weeks i am looking for advice. Can I count spin bike mileage and if so what mileage can I use? I don't want to use the spin bike mileage it seems too high after 60 minutes , Any suggestions or advice? Has anyone counted your indoor training mileage and road mileage toward an annual goal?
Thank you and have wonderful Christmas.
Frank

I think a trainer mile should be good for 2./3 of an on the road mile. Hope you make it to 5000- be sure to send your miles in to me for the annual Iron Crotch/Aluminum Tush list in February's InGear.
Rich Sadler

thank's i will use 2/3 or less . When I am not in the wind I will try to get at least 60 minutes a day on the trainer 4 - 5 days a week . 2 days in the wind . i am pretty sure I did at least 3,000 - 4,000 last year , I missed January due to surgery then I was only a trainer with a cane through February and March .
I hope you have wonderful Christmas.
Frank