public SummaryData(Collection<? extends Coverable> files) {
        for (Coverable file : files) {
            codeLineCount += file.getCodeLineCount();
            codeLinesCoveredCount += file.getCodeLinesCoveredCount();
            branchCount += file.getBranchCount();
            branchesCoveredCount += file.getBranchesCoveredCount();
            functionCount += file.getCodeFunctionCount();
            functionCoveredCount += file.getCodeFunctionCoveredCount();
        }
    }