Interpreting MSBuild Performance Summary Output

Question

I am trying to understand some performance summary output from MSBuild. The results look like this:

Target Performance Summary:
        0 ms  PrepareForRun                             74 calls
        0 ms  Compile                                   74 calls
        ...
        ...
        ...
        ...
    15173 ms  ResolveProjectReferences                  74 calls
    29607 ms  Build                                     75 calls

Task Performance Summary:
        2 ms  CreateCSharpManifestResourceName           6 calls
        2 ms  ResolveKeySource                           1 calls
    ...
    ...
    ...
    ...
     3623 ms  Copy                                     511 calls
     7468 ms  ResolveAssemblyReference                  74 calls
    11234 ms  Exec                                      12 calls
    48600 ms  MSBuild                                  210 calls

Build succeeded.
    0 Warning(s)
    0 Error(s)

Time Elapsed 00:00:29.60

Why does the total time for MSBuild exceed the total elapsed time? The actual stopwatch time to run this build was, in fact, ~29 seconds. Any examples of these summaries that I see online show that the total Task and Target times are same.