select (sum(a.a)/sum(a.ab)) as ab_avg,
sum(a.h) as h_sum,
((sum(a.2B) + sum(a.3B) + sum(a.4B))/sum(a.ab)) as b_avg,
(sum(a.sb) / (sum(a.sb) + sum(a.cs))) as sb_pct,
(sum(a.ab) / (sum(a.hr)) as ab_hr_ratio,
(sum(a.ab) / sum(a.so)) as ab_so_ratio,
b.lastname,
b.firstname
from a, b
where b.id = a.id
group by b.year