The Financial Post reports in its Wednesday edition shares in WestJet tumbled sharply Tuesday on fears that its aggressive expansion plans in 2013 will drag on prices and profitability in the coming quarters. The Post's Scott Deveau writes chief executive officer Gregg Saretsky tried to allay those fears, saying he was comfortable with the carrier's plans to increase it capacity by up to 8.5 per cent this year, including through the launch of new regional carrier Encore on June 24. "Sounds like a buying opportunity to me," Mr. Saretsky said on a conference call when asked about the 7.5-per-cent drop in the company's share price. WestJet said its net income grew 33 per cent to $91.1-million, or 68 cents a share, in the first three months of the year compared with $68.3-million, or 49 cents a share, a year ago. Walter Spracklin, RBC Capital Markets analyst, said WestJet's declining yields and load factor were evidence of the diminishing pricing power Canadian airlines have enjoyed for the past two years. Mr. Saretsky said he had "no visibility" whether the pricing trend would continue into the second half of 2013. WestJet warned it would be taking a charge of up to $70-million when its older aircraft are sold.