Urban/Rural Migration among American Indians and Alaska Natives

I am interested in examining migration patterns among American Indians and Alaska Natives. I would like to be able to characterize migration between rural and urban areas between 2011-2015. CPS data available from Data Ferrett includes the following variables:

MIG_CBST

Migration (1-year) CBSA status description

With the following Ranges:

0 Not in universe, nonmover

1 CBSA

2 non-CBSA

3 Abroad

4 Not Identifiable

MIG_DSCP

Migration (1-year) CBSA status of residence

With the following Ranges:

0 Not in universe, nonmover

1 Principal city of CBSA

2 Balance of a CBSA

3 Non-CBSA

4 Abroad

5 Not identifiable

MIG_MTR1

Previous residence,Recode-Metro Status(Type of Move)

With the following Ranges:

1 Nonmover

2 MSA to MSA

3 MSA to NonMSA

4 NonMSA to MSA

5 NonMSA to NonMSA

6 Abroad to MSA

7 Abroad to NonMSA

8 Not in universe (children under 1 yr old

9 Not Identified

Is there a reason these variables are not included in IPUMS-CPS, and/or does anyone know how to recode the variables using IPUMS-CPS. I would prefer to use data from 2011-2015.