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We used 10 carriers with nationwide networks to make our test as widely applicable as possible. Taking last year's 10 as a starting point we selected the two carriers which had performed best, Tuffnells and De La Rue Parceline.
Both Elan and TNT Overnite failed to deliver on time so we had to give them a chance to atone. Securicor broke our parcel last year and so we had to give this carrier another chance too.
That left five slots to fill. Three large, nationwide carriers de-selected themselves by saying that they could not guarantee next-day delivery in Dundee. So we chose two companies that we did not use last year, Interlink and Carryfast, and added two companies that we did, ANC and Independent Express.
The final place was given to Datapost, the Royal Mail's nextday small parcels/courier service; as market leader in the parcels business the Post Office could not be left out.