The following additional and modified data sets and macro variable contain the input data that are used in this example:

data arc_data;
   input j $12. i $12. cost;
   datalines;
Newcastle   Liverpool   0.5
Birmingham  Liverpool   0.5
Birmingham  Brighton    0.3
London      Liverpool   1.0
London      Brighton    0.5
Exeter      Liverpool   0.2
Exeter      Brighton    0.2
C1          Liverpool   1.0
C1          Brighton    2.0
C1          Birmingham  1.0
C2          Newcastle   1.5
C2          Birmingham  0.5
C2          London      1.5
C3          Liverpool   1.5
C3          Newcastle   0.5
C3          Birmingham  0.5
C3          London      2.0
C3          Exeter      0.2
C4          Liverpool   2.0
C4          Newcastle   1.5
C4          Birmingham  1.0
C4          Exeter      1.5
C5          Birmingham  0.5
C5          London      0.5
C5          Exeter      0.5
C6          Liverpool   1.0
C6          Newcastle   1.0
C6          London      1.5
C6          Exeter      1.5
Bristol     Liverpool   0.6
Bristol     Brighton    0.4
Northampton Liverpool   0.4
Northampton Brighton    0.3
C1          Bristol     1.2
C2          Bristol     0.6
C2          Northampton 0.4
C3          Bristol     0.5
C4          Northampton 0.5
C5          Bristol     0.3
C5          Northampton 0.6
C6          Bristol     0.8
C6          Northampton 0.9
;

data depot_data;
   input depot $12. throughput cost savings;
   datalines;
Newcastle    70000     0 10000
Birmingham   50000     0     .
London      100000     0     .
Exeter       40000     0  5000
Bristol      30000 12000     0
Northampton  25000  4000     0
;

data expand_depot_data;
   input depot $12. throughput cost;
   datalines;
Birmingham   20000  3000
;

%let max_num_depots = 4;