Recession simply means the rate of change of GDP is negative. Hence if GDP falls by 10% and then remains constant, recession has ended. A technical term like GDP should not be used as an indicator of people’s feeling of well being. A famous example is that GDP can be increased if wives demand salary from husbands (for house work) and husbands yield to the demand and pay. Adds nothing to value of goods/services but brings it under accounting for GDP.