“From 1976 to 2000 grazing units fell from 10.1 million to 9.8 million “
The BLM says you are wrong:
“Over time there has been a gradual decrease in the amount of grazing that takes place on BLM-managed land, and that trend continues today. Grazing use on public lands has declined from 18.2 million AUMs in 1954 to 7.9 million AUMs in 2013.” (That is 2.3:1, BTW)
http://www.blm.gov/wo/st/en/prog/grazing.html
Nevada AUMs Authorized 1971-2010
1971: 2,198,371
1981: 1,651,936
1991: 1,693,508
2001: 1,304,781
2010: 1,138,171
http://www.blm.gov/nv/st/en/prog/grazing/animal_unit_months.html
It is multi use. Not grazers only. If you want to you can read the entire FLPMA, its online.
Congress(legislative branch) writes the legislation(FLPMA). The BLM(executive branch) administers and enforces. The courts(judicial branch) arbitrates the conflicts.
But the Posse Comitatus people like you, Bundy, and many others don't recognize the govt(3 branches) so you want to say what the level of grazing will be, or what will or will not be national monuments, or what the endangered species will be, etc, etc. Even though Congress has enacted legislation to deal with all these issues. Congress passed the Antiquities Act, the Endangered Species Act, and FLPMA.
The reality is that disputes between grazers and BLM are few and mostly minor. But there are a very small number like Bundy or Hage who are Posse Comitatus itching for a fight. Consequently, you don't see any other grazers in the trench with Bundy, only militia and oathkeepers.