82 
PRINCIPLES OF BACTERIOLOGY 
If, for example, the total count is 20,000 and neutro- 
philes are 80 per cent, the index is 1. If the total 
count is 20,000 and neutrophiles are 70 per cent, the 
index is +10 (that is, neutrophiles are 10 per cent less 
than they could be with safety). If the total count is 
20,000 and neutrophiles are 90 per cent, the index is 
-10 (that is, neutrophiles are 10 per cent too much for 
safety). The more negative the index, the graver the 
outlook. 
