The Market  Soybean crushing margins improved 5 percent this week as lower soybean costs offset a mild dip in soyoil values while soymeal prices were essentially unchanged. The board crush margin (that is, the margin implied by CBOT soybean, soyoil, and soymeal futures) is up 6.5 percent from last Thursday at $1.48/bushel and are 123 percent above year-ago levels. The crush margin has turned sideways over the past three weeks after a solid rally in March and early April. Seasonally, crush margins tend to remain volatile but relatively steady from May into July, at which point they have rallied sharply in each of the past three years.    The oilshare of the crush margin (that is, the proportion of revenues contributed by the s...