year ended december 31 , 2004 compared to year ended december 31 , 2003 the historical results of operations of pca for the years ended december 31 , 2004 and 2003 are set forth below : for the year ended december 31 , ( in millions ) 2004 2003 change .

for the year ended december 31 , 2004: net sales: 1890.1
income before interest and taxes: 140.5
interest expense net: -29.6
income ( loss ) before taxes: 110.9
( provision ) benefit for income taxes: -42.2
net income ( loss ): 68.7
for the year ended december 31 , 2003: net sales: 1735.5
income before interest and taxes: 96.9
interest expense net: -121.8
income ( loss ) before taxes: -24.9
( provision ) benefit for income taxes: 10.5
net income ( loss ): -14.4
change: net sales: 154.6
income before interest and taxes: 43.6
interest expense net: 92.2
income ( loss ) before taxes: 135.8
( provision ) benefit for income taxes: -52.7
net income ( loss ): 83.1

net sales net sales increased by $ 154.6 million , or 8.9% ( 8.9 % ) , for the year ended december 31 , 2004 from the year ended december 31 , 2003 . net sales increased due to improved sales volumes and prices of corrugated products and containerboard compared to 2003 . total corrugated products volume sold increased 6.6% ( 6.6 % ) to 29.9 billion square feet in 2004 compared to 28.1 billion square feet in 2003 . on a comparable shipment-per-workday basis , corrugated products sales volume increased 7.0% ( 7.0 % ) in 2004 from 2003 . excluding pca 2019s acquisition of acorn in february 2004 , corrugated products volume was 5.3% ( 5.3 % ) higher in 2004 than 2003 and up 5.8% ( 5.8 % ) compared to 2003 on a shipment-per-workday basis . shipments-per-workday is calculated by dividing our total corrugated products volume during the year by the number of workdays within the year . the larger percentage increase was due to the fact that 2004 had one less workday ( 251 days ) , those days not falling on a weekend or holiday , than 2003 ( 252 days ) . containerboard sales volume to external domestic and export customers increased 6.8% ( 6.8 % ) to 475000 tons for the year ended december 31 , 2004 from 445000 tons in 2003 . income before interest and taxes income before interest and taxes increased by $ 43.6 million , or 45.1% ( 45.1 % ) , for the year ended december 31 , 2004 compared to 2003 . included in income before interest and taxes for the year ended december 31 , 2004 is income of $ 27.8 million , net of expenses , attributable to a dividend paid to pca by stv , the timberlands joint venture in which pca owns a 311 20443% ( 20443 % ) ownership interest . included in income before interest and taxes for the year ended december 31 , 2003 is a $ 3.3 million charge for fees and expenses related to the company 2019s debt refinancing which was completed in july 2003 , and a fourth quarter charge of $ 16.0 million to settle certain benefits related matters with pactiv corporation dating back to april 12 , 1999 when pca became a stand-alone company , as described below . during the fourth quarter of 2003 , pactiv notified pca that we owed pactiv additional amounts for hourly pension benefits and workers 2019 compensation liabilities dating back to april 12 , 1999 . a settlement of $ 16.0 million was negotiated between pactiv and pca in december 2003 . the full amount of the settlement was accrued in the fourth quarter of 2003 . excluding these special items , operating income decreased $ 3.4 million in 2004 compared to 2003 . the $ 3.4 million decrease in income before interest and taxes was primarily attributable to increased energy and transportation costs ( $ 19.2 million ) , higher recycled and wood fiber costs ( $ 16.7 million ) , increased salary expenses related to annual increases and new hires ( $ 5.7 million ) , and increased contractual hourly labor costs ( $ 5.6 million ) , which was partially offset by increased sales volume and sales prices ( $ 44.3 million ) . .

Questions:
what were the net sales in 2003?
and what was the income before interest and taxes in that year?
what were, then, those sales without this income?
and considering this year plus the next, what was the combined total of those net sales?

Answers:
1735.5
96.9
1638.6
3625.6