Question: When was the American musical theatre lyricist who sang  "Day by Day" born? 

Context paragraphs:
Stephen Schwartz (composer): Stephen Lawrence Schwartz (born March 6, 1948) is an American musical theatre lyricist and composer.  In a career spanning over four decades, Schwartz has written such hit musicals as "Godspell" (1971), "Pippin" (1972) and "Wicked" (2003).  He has contributed lyrics for a number of successful films, including "Pocahontas" (1995), "The Hunchback of Notre Dame" (1996), "The Prince of Egypt" (1998; music and lyrics) and "Enchanted" (2007).  Schwartz has won the Drama Desk Award for Outstanding Lyrics, three Grammy Awards, three Academy Awards and has been nominated for six Tony Awards.  He received the 2015 Isabelle Stevenson Award, a special Tony Award, for his commitment to serving artists and fostering new talent.

Fred Ebb: Fred Ebb (April 8, 1928 – September 11, 2004) was an American musical theatre lyricist who had many successful collaborations with composer John Kander.  The Kander and Ebb team frequently wrote for such performers as Liza Minnelli and Chita Rivera.

Sybille Pearson: Sybille Pearson (born January 25, 1937, in Prague, Czechoslovakia) is a playwright, musical theatre lyricist and librettist.

Joe Darion: Joe Darion, (30 January 1917 - 6 June 2001) was an American musical theatre lyricist, most famous for "Man of La Mancha."

Gerald Bordman: Gerald Martin Bordman (September 18, 1931 – May 9, 2011) was an American theatre historian, best known for authoring the reference volume "The American Musical Theatre", first published in 1978.  In reviewing an updated version of "American Musical Theatre" in 2011, "Playbill" wrote that the book had "altered the scope of American musical theatre history" and "remained the only book of its kind, and an invaluable one."

Alain Boublil: Alain Boublil (born 5 March 1941) is a Tunisian musical theatre lyricist and librettist, best known for his collaborations with the composer Claude-Michel Schönberg for musicals on Broadway and London's West End.  These include: "La Révolution Française" (1973), "Les Misérables" (1980), "Miss Saigon" (1989), "Martin Guerre" (1996), "The Pirate Queen" (2006), and "Marguerite" (2008).

Fred Alley: Fred Alley (1962–2001) was an American musical theatre lyricist and librettist who died unexpectedly just as his work gained national recognition.  His collaboration on the musical "The Spitfire Grill" with composer James Valcq won the American Academy of Arts and Letters' prestigious Richard Rodgers Production Award for 2001.  Premiered at the George Street Playhouse in New Jersey and produced Off-Broadway by Playwrights Horizons, it received Best Musical nominations from the Outer Critics Circle and Drama League, as well as two Drama Desk nominations.  The cast album was released on Triangle Road Records.

David Zippel: David Joel Zippel (born May 17, 1954) is an American musical theatre lyricist, director and producer.

Day by Day (Godspell song): "Day by Day" is a folk rock ballad from the 1971 Stephen Schwartz and John-Michael Tebelak musical "Godspell".

Robert Ayres Barnet: Robert Ayres Barnet or R. A. Barnet (1853-1933) was an American musical theatre lyricist in New York City and Boston, Massachusetts, in the late 19th and early 20th centuries.  He wrote lyrics for "1492" and "Excelsior Jr." Collaborators included Robert Melville Baker, George Whitefield Chadwick, Edward Warren Corliss, Louis F. Gottschalk, Harry Lawson Heartz, David Kilburn Stevens, Lewis Sabin Thompson, and George Lowell Tracy.  He belonged to the Boston Cadets, and contributed to the group's amateur theatricals.  For example, his "Jack and the Beanstock" premiered in 1896 at Boston's Tremont Theatre.  It was performed by the "Boston Cadets, who always present Barnet's pieces before they are staged professionally.  The new piece is ... a fairy Mother Goose burlesque.  The music is by A.B. Sloane.  ... Augustus Pitou, Klaw & Erlanger, E.E. Rice, and other prominent gentlemen" attended.  The female impersonator Julian Eltinge appeared in the early shows.  Barnet died in New York in 1933.

Supporting paragraphs: Day by Day (Godspell song) Stephen Schwartz (composer)
Answer: March 6, 1948