http://www.who.int/vmnis/indicators/haemoglobin.pdf provides the information.

Thank you Fabian Rohner. This helps.

Dear Theo:
Table 2 in the WHO publication "Haemoglobin concentrations for the diagnosis of anaemia and assessment of severity" is unclear. The first column gives a single altitude. Is that single altitude the beginning of a range, the end of the range, or the mid-point of the range? I don't know. A much clearer description of hemoglobin adjustment for altitude and smoking is given in Sullivan et al. Haemoglobin adjustments to de?ne anaemia. Tropical Medicine and International Health. Volume 13 no 10 pp 1267–1271 October 2008.