This poll is useless if you want to accurately determine when customers joined. Considering Woot rakes in tons of money, they can afford to have at least Oracle 10g - Enterprise Edition as their back-end database, if not DB2.
Here is a query to help you determine when active customers really joined. An active customer is any customer to sign-in anytime in 2012. Enjoy.
select
decode(year_joined,
1, '2004: The Purple Period',
2, '2005-2006: The Early Broccoli ' || CHR(38) || ' Carrots Age',
3, '2007-2009: Wootward Expansion',
4, '2010-2011: The Dawn of the Amazonian Era',
5, '2012: The Whitespace Revolution'
) as period_joined,
total_customers
from (
select
year_joined,
sum(year_joined_count) as total_customers
from (
select
decode(year_joined,
2004, 1,
2005, 2,
2006, 2,
2007, 3,
2008, 3,
2009, 3,
2010, 4,
2011, 4,
2012, 5,
year_joined
) as year_joined,
year_joined_count
from (
select
to_number(to_char(date_joined, 'yyyy')) as year_joined,
count(*) as year_joined_count
from customers
where last_login >= to_date('01-01-2012', 'mm-dd-yyyy')
group by to_number(to_char(date_joined, 'yyyy'))
)
where year_joined between 2004 and 2012
)
group by year_joined
order by year_joined
);
