Elvis Costello released one or two albums a year early in his career but the torrent of the 70s has slowed to a mere trickle. Over the past six years there have only been three albums - still not bad going by today's standards, which demand singles, videos and months of promotion.
But, on the release of latest solo album, 2010's National Ransom, Costello announced he would not make any more studio records.
"There's no rule that says you have to record everything that you write," the brilliant songwriter elaborates over the phone. "My comment was to do with the use of my own time.
"It's often down to how much time there actually is in any one year to do the things that you want to do and be with your family. Most of my work is now performing."
Last year he joined forces with hip-hop crew the Roots, led by drummer Ahmir "Questlove" Thompson, to write and record the cross-genre collaboration Wise Up Ghost. This startling album, full of syncopated funk patterns, stabbing guitar and sudden bursts of brass was, without doubt, one of the most interesting outings of last year.
The collaboration came together in a year of experimental sessions. The unlikely pair considered reworking Costello's oldies but soon decided on new material.
"Quest and I hardly had a conversation about the music ahead of the recording," says the London- born musician, who turns 60 late this year. "We just got together and played. Later when we were answering questions about the record I discovered we had a lot of the same experiences growing up."
While Costello's output has diminished lately, he's still spending plenty of time in the studio. Late last year he released a seven-track EP of remixed tracks from Wise Up Ghost called Wise Up: Thought. He's there playing ukulele, under the nom de plume Howard Coward, on his multimillion-record-selling jazz diva wife Diana Krall's recent album Glad Rag Doll.
And you can hear him sing Funny Little Tragedy on the recent Gov't Mule album, Shout.
On the other hand, Costello's live appearances have increased exponentially over the past few years. When we talked a few weeks ago he was in Osaka, Japan, performing his audience participation Spectacular Spinning Songbook gigs. "That was probably the last show for the foreseeable future," he says. "The (Spinning Songbook) wheel has pretty much travelled everywhere except Texas (and unfortunately he wasn't able to bring it to Perth in February 2013 during his last Australian tour). But who knows what the future holds."
Costello also recently played a solo tour of the north-eastern US, which the man with the fearsomely large back catalogue of songs said were some of the most interesting shows he's done.
"I took a new approach - sort of the opposite to the wheel really. I had a thread linking the songs in my head that I didn't tell people about until I got on stage. It gave me an opportunity to play quite a lot of songs that I don't often perform."
The man born Declan McManus is back on the road next month with bookings lined up across North America that alternate shows with both the Imposters and the Roots. Immediately after, he heads Down Under for a seven-date tour starting at the West Coast Blues 'n'Roots Festival in Fremantle on April 13.
As usual, Costello will have no shortage of material to draw on. "With the random nature of the wheel the Imposters and I have learnt a lot of songs. We probably have three or four times as many songs at our disposal at any one moment than most groups. Just now we've got seven songs from Wise Up Ghost that don't bear any resemblance to the recorded versions because it's us playing them."
For the future, the former enfant terrible of the New Wave era is working with his long-time idol Burt Bacharach on a stage musical based on their 1998 collaboration Painted From Memory. Work is already in hand with scriptwriter Chuck Lorre, who created TV sitcom The Big Bang Theory.
"It's not as though Painted From Memory was a big hit record, so it's not like one of those jukebox musicals with hit after hit," Costello explains. "We've written 12 new songs to give structure to the story but it remains to be seen if they will come out as a record."