My company was needing a state drop down in a Rails app to record license plate states. As a higher-education institution, there is the possibility of Canadian and Mexican vehicles as well. Not finding a Rails-ready hash for the grouped_options_for_select method, I converted an HTML version to a Rails-ready version for my reference and perhaps the benefit of others.
Note: if you use the grouped_options_for_select method, realize that the value isn’t automatically filled in by the ActionView helper for existing method values. You must include the selected_key = @model_object.method parameter
{"United States" =>
[["AL", "Alabama (AL)"],
["AK", "Alaska (AK)"],
["AZ", "Arizona (AZ)"],
["AR", "Arkansas (AR)"],
["CA", "California (CA)"],
["CO", "Colorado (CO)"],
["CT", "Connecticut (CT)"],
["DE", "Delaware (DE)"],
["DC", "District of Columbia (DC)"],
["FL", "Florida (FL)"],
["GA", "Georgia (GA)"],
["GU", "Guam (GU)"],
["HI", "Hawaii (HI)"],
["ID", "Idaho (ID)"],
["IL", "Illinois (IL)"],
["IN", "Indiana (IN)"],
["IA", "Iowa (IA)"],
["KS", "Kansas (KS)"],
["KY", "Kentucky (KY)"],
["LA", "Louisiana (LA)"],
["ME", "Maine (ME)"],
["MD", "Maryland (MD)"],
["MA", "Massachusetts (MA)"],
["MI", "Michigan (MI)"],
["MN", "Minnesota (MN)"],
["MS", "Mississippi (MS)"],
["MO", "Missouri (MO)"],
["MT", "Montana (MT)"],
["NE", "Nebraska (NE)"],
["NV", "Nevada (NV)"],
["NH", "New Hampshire (NH)"],
["NJ", "New Jersey (NJ)"],
["NM", "New Mexico (NM)"],
["NY", "New York (NY)"],
["NC", "North Carolina (NC)"],
["ND", "North Dakota (ND)"],
["OH", "Ohio (OH)"],
["OK", "Oklahoma (OK)"],
["OR", "Oregon (OR)"],
["PA", "Pennyslvania (PA)"],
["PR", "Puerto Rico (PR)"],
["RI", "Rhode Island (RI)"],
["SC", "South Carolina (SC)"],
["SD", "South Dakota (SD)"],
["TN", "Tennessee (TN)"],
["TX", "Texas (TX)"],
["UT", "Utah (UT)"],
["VT", "Vermont (VT)"],
["VA", "Virginia (VA)"],
["VI", "Virgin Islands (VI)"],
["WA", "Washington (WA)"],
["WV", "West Virginia (WV)"],
["WI", "Wisconsin (WI)"],
["WY", "Wyoming (WY)"]],
"Canada" =>
[["AB", "Alberta (AB)"],
["BC", "British Columbia (BC)"],
["MB", "Manitoba (MB)"],
["NB", "New Brunswick (NB)"],
["NL", "Newfoundland and Labrador (NL)"],
["NT", "Northwest Territories (NT)"],
["NS", "Nova Scotia (NS)"],
["NU", "Nunavut (NU)"],
["PE", "Prince Edward Island (PE)"],
["SK", "Saskatchewan (SK)"],
["ON", "Ontario (ON)"],
["QC", "Quebec (QC)"],
["YT", "Yukon (YT)"]],
"Mexico" =>
[["AGS", "Aguascalientes (AGS)"],
["BCN", "Baja California Norte (BCN)"],
["BCS", "Baja California Sur (BCS)"],
["CAM", "Campeche (CAM)"],
["CHIS", "Chiapas (CHIS)"],
["CHIH", "Chihuahua (CHIH)"],
["COAH", "Coahuila (COAH)"],
["COL", "Colima (COL)"],
["DF", "Distrito Federal (DF)"],
["DGO", "Durango (DGO)"],
["GTO", "Guanajuato (GTO)"],
["GRO", "Guerrero (GRO)"],
["HGO", "Hidalgo (HGO)"],
["JAL", "Jalisco (JAL)"],
["EDM", "México - Estado de (EDM)"],
["MICH", "Michoacán (MICH)"],
["MOR", "Morelos (MOR)"],
["NAY", "Nayarit (NAY)"],
["NL", "Nuevo León (NL)"],
["OAX", "Oaxaca (OAX)"],
["PUE", "Puebla (PUE)"],
["QRO", "Querétaro (QRO)"],
["QROO", "Quintana Roo (QROO)"],
["SLP", "San Luis Potosí (SLP)"],
["SIN", "Sinaloa (SIN)"],
["SON", "Sonora (SON)"],
["TAB", "Tabasco (TAB)"],
["TAMPS", "Tamaulipas (TAMPS)"],
["TLAX", "Tlaxcala (TLAX)"],
["VER", "Veracruz (VER)"],
["YUC", "Yucatán (YUC)"],
["ZAC", "Zacatecas (ZAC)"]]
}