Just looked up my CBC results taken for a hand surgery I am having later this week. These three tests were low:

RBC 3.89 m/uL range: 4.40 - 6.00 m/uL
HGB 12.9 g/dL range: 14.0 - 18.0 g/dL
HCT 38.2 % range: 41.0 - 51.0 %

I guess injecting once a month isn't doing the job on the B12.