### Database Schema:
CREATE TABLE matchs (
	Div	TEXT	NULL,
	Date	DATE	NULL,
	HomeTeam	TEXT	NULL,
	AwayTeam	TEXT	NULL,
	FTHG	INTEGER	NULL,
	FTAG	INTEGER	NULL,
	FTR	TEXT	NULL,
	season	INTEGER	NULL,
	foreign key (Div) references divisions (division)
);

CREATE TABLE divisions (
	division	TEXT	NOT NULL	PRIMARY KEY,
	name	TEXT	NULL,
	country	TEXT	NULL
);

### User's Query:
What percentage of matches played on 2005/07/30 belong to the F1 division?

### Extra Knowledge:
Division refers to Div; DIVIDE(COUNT(Div = 'F1', Date = '2005/07/30'), COUNT(Div, Date = '2005/07/30')) as percentage;
SELECT CAST(SUM(CASE WHEN Div = 'F1' THEN 1 ELSE 0 END) AS REAL) * 100 / COUNT(Div) FROM matchs WHERE Date = '2005-07-30' 