Linking Roster Items across Rounds in the NLSY97

SAS code

position2 = 0;
if R1uid2 = R2uid1, then position2 = 1;
if R1uid2 = R2uid2, then position2 = 2;
if R1uid2 = R2uid3, then position2 = 3;
if R1uid2 = R2uid4, then position2 = 4;
if R1uid2 = R2uid5, then position2 = 5;
if R1uid2 = R2uid6, then position2 = 6;
if R1uid2 = R2uid7, then position2 = 7;
if R1uid2 = R2uid8, then position2 = 8;
if R1uid2 = R2uid9, then position2 = 9;
if R1uid2 = R2uid10, then position2 = 10;
if R1uid2 = R2uid11, then position2 = 11;
if R1uid2 = R2uid12, then position2 = 12;
if R1uid2 = R2uid13, then position2 = 13;
if R1uid2 = R2uid14, then position2 = 14;

Note that more experienced SAS programmers can use arrays to achieve the same result.