United States. Sherwin-Williams Company announced its financial results for the second quarter ended June 30, 2018. Compared to the same period in 2017, consolidated net sales increased $1.04 billion, or 27.8%, to $4.77 billion in the quarter and increased $2.24 billion, or 34.5%, to $8.74 billion in six months primarily due to the addition of Valspar sales, higher paint sales volume at The Americas Group and increases in sales prices.
Valspar's incremental sales of April and May 2018 increased net sales by 21.0% in the quarter. Valspar's incremental sales for the five months ended May 2018 increased net sales by 28.5% during the first six months. As a result of the new revenue standard (ASC 606) adopted in the first quarter of 2018, some advertising support that was previously classified as sales, general and administrative expenses is now classified as a reduction in revenue with no effect on net income.
The new revenue standard reduced consolidated net sales by about 1.1% in the quarter and .6% in the first six months.
Net sales at The Americas Group increased 7.7% to $2.63 billion in the quarter and increased 7.2% to $4.71 billion in six months primarily due to higher architectural paint sales volume in most end market segments and increases in sales prices. Changes in the currency conversion rate decreased the Group's net sales by .5% and .3% in the quarter and six months, respectively. Net sales of U.S. and Canadian stores open for more than twelve months increased 6.8% in the quarter and 6.1% in six months from comparable periods last year. Segment earnings increased $37.2 million to $569.9 million in the quarter and increased $69.4 million to $907.3 million in six months primarily due to higher paint sales volume and increases in sales prices, partially offset by higher raw material costs.
Segment profit as a percentage of net sales decreased in the quarter to 21.7% from 21.9% last year due to improved operating margins not sufficient to offset losses from unfavorable foreign currency transactions and a profit settlement gain after the second quarter of 2017. In the first six months, segment earnings as a percentage of net sales increased to 19.3% of net sales from 19.1% last year due to higher paint sales volume and increases in sales prices partially offset by higher raw material costs.
