During 2011, P Company discovered that the ending inventories reported on its financial statements were incorrect by the following amounts:
2009 $120,000 understated
2010 $150,000 overstated
P uses the periodic inventory system to ascertain year-end quantities that are converted to dollar amounts using the FIFO cost method. Prior to any adjustments for these errors and ignoring income taxes, what would be P's retained earnings at January 1, 2011 ?