$Psychemedics (PMD.US)$Revenue fell sharply for two consecut...

$Psychemedics (PMD.US)$Revenue fell sharply for two consecutive years in 2019 and 2020, and only a small portion recovered in the next two years. Operating profit was lost for one year in 2020, fluctuated around the profit and loss line for the next two years, and net profit was a continuous loss for 3 years.