Blue chip freight company Mainfreight also helped give the index a boost, gaining 1 per cent to $84.00, continuing its strong run. Fellow freight company Freightways was up 0.08 per cent at $12.67. Freightways has also been a strong performer, its shares gaining 21 per cent in the five months to the end of July. Contact Energy, whose shares rose 22 per cent over that period, was up 0.4 per cent on Wednesday at $8.41. NZ Refining, which rose 82 per cent in that time, jumped 4.8 per cent to 86c. LAWRENCE SMITH/Stuff The New Zealand sharemarket got a boost from blue chips and a record high for the S&P 500 Index on Wall Street.