anchor.diff:  41700,"San Antonio-New Braunfels, TX",B
   41740,"San Diego-Carlsbad, CA",B
   41860,"San Francisco-Oakland-Hayward, CA",B
  -41900,"San Germn, PR",B
  +41900,"San Germán, PR",B
   41940,"San Jose-Sunnyvale-Santa Clara, CA",B
   41980,"San Juan-Carolina-Caguas, PR",B
   41999,"Not in metropolitan area, OR",B
  
positive.code: 31860,"Mankato-North Mankato, MN",B
  31900,"Mansfield, OH",B
  31999,"Not in metropolitan area, NE",B
  32420,"Mayagez, PR",B
  32580,"McAllen-Edinburg-Mission, TX",B
  32780,"Medford, OR",B
  32820,"Memphis, TN-MS-AR",B
  
negative.code: 0699999,"Nonmetropolitan, nonmicropolitan",M
  0814500,"Boulder, CO",M
  0814720,"Breckenridge, CO",M
  0815860,"Cañon City, CO",M
  0817820,"Colorado Springs, CO",M
  0818780,"Craig, CO",M
  0819740,"Denver-Aurora-Lakewood, CO",M
  