Last 6 years of stats:

2015 Number of 1st choice apps 11,186 number of ram tags 204 number of rams killed 110 11,186 apps divided by 204 tags = 55 years to get a tag for all
2016 Number of 1st choice apps 11,672 number of ram tags 229 number of rams killed 127 11,672 apps divided by 229 tags = 51 years to get a tag for all
2017 Number of 1st choice apps 12,708 number of ram tags 238 number of rams killed 137 12,708 apps divided by 238 tags = 53 years to get a tag for all
2018 Number of 1st choice apps 23,637 number of ram tags 244 number of rams killed 244 23,637 divided by 244 tags = 97 years to get a tag for all
2019 Number of 1st choice apps 16,845 number of ram tags 244 number of rams killed 244(odd they match 2018) 16,845 divided by 244 = 69 years
2020 Number of 1st choice apps 18,308 number of ram tags 230 number of rams killed 148 18,308 divided by 230 = 80 years to get a tag for all

Not looking good for thinking if you apply for 20 years that you have a smoking good chance for a tag. But thanks for the application fees along the way.