One way to study IBD’s Top World Stocks table on this page is to see which sectors are well represented. In Thursday’s paper, software stocks grabbed the largest share, occupying five of the 10 slots within the elite list. The sector has performed well in this year’s choppy market. In Thursday’s edition, the software sector ranked No. 5 in mid- to long-term performance and was up 13.4% since Jan. 1.