NEW DELHI : The Centre on Monday said the average number of samples being tested per day for COVID-19 has gone up in Delhi from 5,481 to 18,766 in about a month and in spite of increased testing, the positivity rate has declined from around 30 per cent to 10 per cent in the last three weeks.The government also said that the national positivity rate, percentage of samples testing coronavirus positive from the total number of samples, has also reduced and now stands at 6.73 per cent.The Union, state and union territory governments have made a joint and coordinated effort to effectively manage the COVID-19 pandemic in the country, the Union health ministry said in a statement.As part of the coordinated efforts, the Union government has.