re·gret·ta·bly 
/rɪˈgrɛtəbli/ adverb
/rɪˈgrɛtəbli/ adverb [more regrettably; most regrettably] 1 — used to say that something is disappointing or regrettable ▪ Regrettably [=unfortunately], I cannot go. ▪ Regrettably, the movie theater was shut down. 2 : to an extent that causes disappointment or regret
▪ There has been a regrettably [=disappointingly] large decline in wages. ▪ The progress of the work was regrettably slow.
▪ There has been a regrettably [=disappointingly] large decline in wages. ▪ The progress of the work was regrettably slow.
