They have been trying to boost their performance by shortening the duration (a measure that takes into account not just a bond's maturity but the interest it pays) of their portfolios.

ECONOMIST: Bond bombshell

Backup generators are filthy, wasteful and prone to performance problems depending on the frequency and duration of electric grid outages.

FORBES: Backup Generators Are the Bad and Ugly of Decentralized Energy

For instance, InsideTrip awards different scores for the duration of a flight and the airline's on-time performance, its lost-luggage track record, even the amount of legroom aboard planes.

FORBES: Magazine Article