My first piece of advice would be to ignore statistics.
I personally believe that age issues in marriage are the result of immaturity and inexperience. Some are simply not willing or able to cope with the demands of marriage (emotional, physical, mental, financial, families, children, death & taxes -etc.) Some confuse lust with love. The thing is, middle aged people can make those mistakes as well.
If you feel confident in your relationship and you're both willing to give 200%... Not to mention respect that commitment as one that's FOR LIFE.... You may be ready. Ultimately, the decision is yours and in a solid relationship, there shouldn't be any need to rush.