Stocks climbed in midday trading Monday as Wall Street celebrates the bull market turning 6 years old. The Dow was up more than 100 points. Major credit agencies including Equifax (EFX), Experian and TransUnion have agreed to change the way they handle data. Consumer advocates have long sought to overhaul how 'credit scores' were determined including medical debt. McDonald's (MCD) is bouncing back after opening lower on weak sales worldwide. The fast-food giant reported February sales fell more than expected both globally and in the U.S. Alcoa (AA) is down sharply after announcing it will buy metals producer RTI International (RTI). The all-stock deal is worth $1.5 billion and is expected to close in the next 3 to 6 months. Shares of RTI are spiking 40%.