Database schema:

CREATE TABLE actor (
	"ActorID" INTEGER -- example: ['2', '1'],
	"Name" TEXT -- example: ['John Travolta', 'Kirstie Alley'],
	"Date of Birth" DATE -- example: ['1954-02-18', '1951-01-12'],
	"Birth City" TEXT -- example: ['Englewood', 'Wichita'],
	"Birth Country" TEXT -- example: ['West Germany', 'USA'],
	"Height (Inches)" INTEGER -- example: ['67', '74'],
	"Biography" TEXT -- example: ['John Joseph Travolta was born in Englewood, New Je', 'Long a vital, respected lady of the classic and co'],
	"Gender" TEXT -- example: ['Male', 'Female'],
	"Ethnicity" TEXT -- example: ['White', 'African American'],
	"NetWorth" TEXT -- example: ['$40,000,000.00', '$250,000,000.00'],
	PRIMARY KEY ("ActorID")
)


CREATE TABLE characters (
	"MovieID" INTEGER -- example: ['2', '1'],
	"ActorID" INTEGER -- example: ['2', '1'],
	"Character Name" TEXT -- example: ['Mollie', 'James'],
	"creditOrder" INTEGER -- example: ['2', '1'],
	pay TEXT -- example: ['$5,000,000.00', '$60,000,000.00'],
	screentime TEXT -- example: ['0:32:30', '0:32:15'],
	PRIMARY KEY ("MovieID", "ActorID"), 
	CONSTRAINT fk_characters_actor FOREIGN KEY("ActorID") REFERENCES actor ("ActorID"),
	CONSTRAINT fk_characters_movie FOREIGN KEY("MovieID") REFERENCES movie ("MovieID")
)


CREATE TABLE movie (
	"MovieID" INTEGER -- example: ['2', '1'],
	"Title" TEXT -- example: ["Look Who's Talking", 'Driving Miss Daisy'],
	"MPAA Rating" TEXT -- example: ['PG-13', 'PG'],
	"Budget" INTEGER -- example: ['7500000', '13000000'],
	"Gross" INTEGER -- example: ['145793296', '296000000'],
	"Release Date" TEXT -- example: ['1989-12-13', '1989-10-12'],
	"Genre" TEXT -- example: ['Romance', 'Comedy'],
	"Runtime" INTEGER -- example: ['93', '99'],
	"Rating" REAL -- example: ['5.9', '7.4'],
	"Rating Count" INTEGER -- example: ['73638', '91075'],
	"Summary" TEXT -- example: ['After a single, career-minded woman is left on her', 'An old Jewish woman and her African-American chauf'],
	PRIMARY KEY ("MovieID")
)

Question: How much longer in percentage is the screen time of the most important character in Batman than the least important one?
Evidence: most important character refers to max(screentime); least important character refers to min(screentime); movie Batman refers to title = 'Batman'; percentage = divide(subtract(max(screentime) , min(screentime)) , min(screentime)) * 100%

SQL:
SELECT (MAX(CAST(SUBSTR(T2.screentime, 3, 2) AS REAL)) - MIN(CAST(SUBSTR(T2.screentime, 3, 2) AS REAL))) * 100 / MIN(CAST(SUBSTR(T2.screentime, 3, 2) AS REAL)) FROM movie AS T1 INNER JOIN characters AS T2 ON T1.MovieID = T2.MovieID WHERE T1.Title = 'Batman'