I can’t figure the below maths out.

"Assuming that moving 1000 steps moved the focuser 40mm then you know that your focuser moves 4 microns (0.004mm) per step. "

If I divide 40 by 1000 I get 0.04 and not 0.004 as stated by the above instructions.

Please help me to understand the Maths.

Regards,

Simon