Guesstimate: 2000. But info is a bit scarce - You're better off asking a French person.
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Er... this will be your actual bike, no? Listed by the seller as 1999.
http://www.moredirt.co.uk/ratebike.php?id=1474
In which case, ignore all of the following
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The earlier BMiXs (yellow, red?, dark blue, chrome) had a matching unicrown fork; the later ones (seen them in yellow, red, blue and black) had a matching segmented fork, like yours.
But yours has red frame and yellow fork together, so....?
AFAIK, the last bike with the unicrown fork was the chrome one in 1999;
They also made some weird, box-section aluminium BMXs (20" and 24") that used the segmented fork. Not sure if these were sold in the same years as the BMiX, or if they came later.
The dates listed on BMX Museum are USUALLY quite accurate, but you can see there are 3 different versions claimed for 1999:
1999: Chrome BMiX with unicrown fork.
1999: Yellow BMiX with segmented fork.
1999: Yours, in red.
2001: Yellow box-section aluminium thing with segmented BMiX fork.
I would guess that the BMiX with segmemted fork was introduced in 1999 & was sold alongside the box-section frame for a few years. Alu thing in 20" and 24"; BMiX in 26". Same fork. Various colors, blah blah...
Hope that helps - It's early morning here, bright daylight & I'm bored .
Waiting for the rest of the world to wake up, so we can go for a ride