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Officials say the worst back ups have been alleviated, but challenges remain as countermeasures continue to be implemented.
Los Angeles Mayor Eric Garcetti's office says there are "plenty of trucks and drivers."
More needs to be done about these "unfair and unreasonable" fees, according to a joint letter from 94 industry organizations.
The parcel giant reported improved profitability across all business units in the first quarter 2015, thanks primarily to new pricing initiatives, revenue management and strong growth in international volumes.