public long getEstimatedDuration() {
List<RunT> builds = getLastBuildsOverThreshold(3, Result.UNSTABLE);
if (builds.isEmpty()) return -1;
long totalDuration = 0;
for (RunT b : builds) {
totalDuration += b.getDuration();
}
if (totalDuration == 0) return -1;
return Math.round((double) totalDuration / builds.size());
}
