### Database Schema:
CREATE TABLE gasstations (
	GasStationID	INTEGER	NOT NULL	PRIMARY KEY,
	ChainID	INTEGER	NULL,
	Country	TEXT	NULL,
	Segment	TEXT	NULL
);

CREATE TABLE customers (
	CustomerID	INTEGER	NOT NULL	PRIMARY KEY,
	Segment	TEXT	NULL,
	Currency	TEXT	NULL
);

CREATE TABLE yearmonth (
	CustomerID	INTEGER	NOT NULL	PRIMARY KEY,
	Date	TEXT	NOT NULL	PRIMARY KEY,
	Consumption	REAL	NULL,
	foreign key (CustomerID) references customers (CustomerID)
);

CREATE TABLE products (
	ProductID	INTEGER	NOT NULL	PRIMARY KEY,
	Description	TEXT	NULL
);

CREATE TABLE transactions_1k (
	TransactionID	INTEGER	NULL	PRIMARY KEY,
	Date	DATE	NULL,
	Time	TEXT	NULL,
	CustomerID	INTEGER	NULL,
	CardID	INTEGER	NULL,
	GasStationID	INTEGER	NULL,
	ProductID	INTEGER	NULL,
	Amount	INTEGER	NULL,
	Price	REAL	NULL
);

### User's Query:
For the customer who paid 634.8 in 2012/8/25, what was the consumption decrease rate from Year 2012 to 2013?

### Extra Knowledge:
'2012/8/24' can be represented by '2012-08-24'; Consumption decrease rate = (consumption_2012 - consumption_2013) / consumption_2012
SELECT CAST(SUM(IIF(SUBSTR(Date, 1, 4) = '2012', Consumption, 0)) - SUM(IIF(SUBSTR(Date, 1, 4) = '2013', Consumption, 0)) AS FLOAT) / SUM(IIF(SUBSTR(Date, 1, 4) = '2012', Consumption, 0)) FROM yearmonth WHERE CustomerID = ( SELECT T1.CustomerID FROM transactions_1k AS T1 INNER JOIN gasstations AS T2 ON T1.GasStationID = T2.GasStationID WHERE T1.Date = '2012-08-25' AND T1.Price = 634.8 )