Effective office rents in Manhattan rose during the second quarter as asking prices and concessions headed in different directions. Year-over-year, however, incentives like free rent and cash offered to tenants to build out their spaces continue to outpace the growth in asking rents. Across the borough’s three office submarkets, effective rents grew 4.07 percent from the beginning of the year to $67.44 per square foot, according to CompStak data provided to The Real Deal.