=INDEX(C:C,COUNTA(C:C))

Customer ID Custmer Name    Item Number Item Name   Date        Desired Results
1           Bob             222         Paper       1/1/2016    X
1           Bob             111         Tape        1/1/2017    X
1           Bob             333         Pen         1/1/2018    X
4           Greg            333         Pen         1/1/2015
4           Greg            111         Tape        1/1/2016
6           Chris           111         Tape        1/1/2015    X
6           Chris           333         Pen         1/1/2018    X
8           Luke            333         Pen         1/1/2013
8           Luke            333         Pen         1/1/2014
8           Luke            222         Paper       1/1/2015
8           Luke            111         Tape        1/1/2016
8           Luke            111         Tape        1/1/2018
9           Tom             333         Pen         1/1/2013    X