Graybar, St. Louis, MO, reported sales of $5.009 billion in 2006, up 16.6% from last year. Profit was $57 million, more than double the year before.   ; Growth in the electrical market increased 16.6%. Electrical sales were strong in the construction sector. Sales in the comm/data market rose 17% year-over-year.   ; In an SEC filing, Graybar attributed the increase in sales to demand in the electrical and communications/data markets. Also, copper-based products, mainly wire and cable, went up in price in the past year, positively impacting sales.   ; Profit growth was attributed to double-digit growth in gross margin, coupled with attention to controlling expenses. Graybar also reported productivity gains as a result of the company's new technology platform.