Although a formal environmental impact assessment has not yet been done, it should not be assumed that thiomersal-free presentations of vaccines will yield a positive net effect on the environment.
虽然尚未开展正式的环境影响评估，但不应假设无硫柳汞的疫苗对环境产生的净效果是正面的。
2
Some profit indexes like income of each section, net asset yield and net profit have acted as the scaled standard of listed company for a long time.