### Database Schema:
CREATE TABLE user_reviews (
	App	TEXT	NULL,
	Translated_Review	TEXT	NULL,
	Sentiment	TEXT	NULL,
	Sentiment_Polarity	TEXT	NULL,
	Sentiment_Subjectivity	TEXT	NULL,
	foreign key (App) references playstore (App)
);

CREATE TABLE playstore (
	App	TEXT	NULL,
	Category	TEXT	NULL,
	Rating	REAL	NULL,
	Reviews	INTEGER	NULL,
	Size	TEXT	NULL,
	Installs	TEXT	NULL,
	Type	TEXT	NULL,
	Price	TEXT	NULL,
	`Content Rating`	TEXT	NULL,
	Genres	TEXT	NULL
);

### User's Query:
List down application that have not been updated since 2015. What is the percentage of this application having more negative sentiment than positive sentiment?

### Extra Knowledge:
percentage = DIVIDE(SUBTRACT(SUM(Sentiment = 'Positive')), (SUM(Sentiment = 'Negative'))), (SUM(Sentiment = 'Negative')) as percent; Last Updated>'2015';
SELECT CAST((( SELECT COUNT(*) Po FROM playstore AS T1 INNER JOIN user_reviews AS T2 ON T1.App = T2.App WHERE SUBSTR(T1."Last Updated", -4, 4) > '2015' AND T2.Sentiment = 'Positive' ) - ( SELECT COUNT(*) Ne FROM playstore AS T1 INNER JOIN user_reviews AS T2 ON T1.App = T2.App WHERE SUBSTR(T1."Last Updated", -4, 4) > '2015' AND T2.Sentiment = 'Negative' )) AS REAL) * 100 / ( SELECT COUNT(*) NUM FROM playstore AS T1 INNER JOIN user_reviews AS T2 ON T1.App = T2.App WHERE SUBSTR(T1."Last Updated", -4, 4) > '2015' )