Database schema:

CREATE TABLE "order" (
	order_id INTEGER DEFAULT 0 NOT NULL -- example: ['29402', '29401'],
	account_id INTEGER NOT NULL -- example: ['2', '1'],
	bank_to TEXT NOT NULL -- bank of the recipient, example: ['YZ', 'ST'],
	account_to INTEGER NOT NULL -- account of the recipient, example: ['87144583', '89597016'],
	amount REAL NOT NULL -- debited amount, example: ['2452.0', '3372.7'],
	k_symbol TEXT NOT NULL -- characterization of the payment, example: ['SIPO', 'UVER'],
	PRIMARY KEY (order_id), 
	CONSTRAINT fk_order_account FOREIGN KEY(account_id) REFERENCES account (account_id)
)


CREATE TABLE account (
	account_id INTEGER DEFAULT 0 NOT NULL -- account id, example: ['2', '1'],
	district_id INTEGER DEFAULT 0 NOT NULL -- location of branch, example: ['1', '18'],
	frequency TEXT NOT NULL -- example: ['POPLATEK TYDNE', 'POPLATEK MESICNE'],
	date DATE NOT NULL -- example: ['1993-02-26', '1995-03-24'],
	PRIMARY KEY (account_id), 
	CONSTRAINT fk_account_district FOREIGN KEY(district_id) REFERENCES district (district_id)
)


CREATE TABLE card (
	card_id INTEGER DEFAULT 0 NOT NULL -- credit card id, example: ['2', '1'],
	disp_id INTEGER NOT NULL -- disposition id, example: ['9', '19'],
	type TEXT NOT NULL -- example: ['gold', 'classic'],
	issued DATE NOT NULL -- example: ['1998-03-13', '1998-10-16'],
	PRIMARY KEY (card_id), 
	CONSTRAINT fk_card_disp FOREIGN KEY(disp_id) REFERENCES disp (disp_id)
)


CREATE TABLE client (
	client_id INTEGER NOT NULL -- example: ['2', '1'],
	gender TEXT NOT NULL -- example: ['M', 'F'],
	birth_date DATE NOT NULL -- example: ['1970-12-13', '1945-02-04'],
	district_id INTEGER NOT NULL -- location of branch, example: ['1', '18'],
	PRIMARY KEY (client_id), 
	CONSTRAINT fk_client_district FOREIGN KEY(district_id) REFERENCES district (district_id)
)


CREATE TABLE disp (
	disp_id INTEGER NOT NULL -- disposition id, example: ['2', '1'],
	client_id INTEGER NOT NULL -- example: ['2', '1'],
	account_id INTEGER NOT NULL -- example: ['2', '1'],
	type TEXT NOT NULL -- example: ['OWNER', 'DISPONENT'],
	PRIMARY KEY (disp_id), 
	CONSTRAINT fk_disp_account FOREIGN KEY(account_id) REFERENCES account (account_id),
	CONSTRAINT fk_disp_client FOREIGN KEY(client_id) REFERENCES client (client_id)
)


CREATE TABLE district (
	district_id INTEGER DEFAULT 0 NOT NULL -- location of branch, example: ['2', '1'],
	"A2" TEXT NOT NULL -- district_name, example: ['Hl.m. Praha', 'Benesov'],
	"A3" TEXT NOT NULL -- region, example: ['central Bohemia', 'Prague'],
	"A4" TEXT NOT NULL -- number of inhabitants, example: ['88884', '1204953'],
	"A5" TEXT NOT NULL -- no. of municipalities with inhabitants < 499, example: ['0', '80'],
	"A6" TEXT NOT NULL -- no. of municipalities with inhabitants 500-1999, example: ['0', '26'],
	"A7" TEXT NOT NULL -- no. of municipalities with inhabitants 2000-9999, example: ['0', '6'],
	"A8" INTEGER NOT NULL -- no. of municipalities with inhabitants > 10000, example: ['2', '1'],
	"A9" INTEGER NOT NULL -- example: ['5', '1'],
	"A10" REAL NOT NULL -- ratio of urban inhabitants, example: ['46.7', '100.0'],
	"A11" INTEGER NOT NULL -- average salary, example: ['8507', '12541'],
	"A12" REAL -- unemployment rate 1995, example: ['0.2', '1.6'],
	"A13" REAL NOT NULL -- unemployment rate 1996, example: ['1.85', '0.43'],
	"A14" INTEGER NOT NULL -- no. of entrepreneurs per 1000 inhabitants, example: ['132', '167'],
	"A15" INTEGER -- no. of committed crimes 1995, example: ['85677', '2159'],
	"A16" INTEGER NOT NULL -- no. of committed crimes 1996, example: ['2674', '99107'],
	PRIMARY KEY (district_id)
)


CREATE TABLE loan (
	loan_id INTEGER DEFAULT 0 NOT NULL -- example: ['4961', '4959'],
	account_id INTEGER NOT NULL -- example: ['2', '19'],
	date DATE NOT NULL -- example: ['1996-04-29', '1994-01-05'],
	amount INTEGER NOT NULL -- example: ['80952', '30276'],
	duration INTEGER NOT NULL -- example: ['24', '12'],
	payments REAL NOT NULL -- monthly payments, example: ['2523.0', '3373.0'],
	status TEXT NOT NULL -- example: ['A', 'B'],
	PRIMARY KEY (loan_id), 
	CONSTRAINT fk_loan_account FOREIGN KEY(account_id) REFERENCES account (account_id)
)


CREATE TABLE trans (
	trans_id INTEGER DEFAULT 0 NOT NULL -- transaction id, example: ['5', '1'],
	account_id INTEGER DEFAULT 0 NOT NULL -- example: ['2', '1'],
	date DATE NOT NULL -- date of transaction, example: ['1995-04-13', '1995-03-24'],
	type TEXT NOT NULL -- +/- transaction, example: ['PRIJEM', 'VYDAJ'],
	operation TEXT -- mode of transaction, example: ['VKLAD', 'PREVOD Z UCTU'],
	amount INTEGER NOT NULL -- amount of money, example: ['3679', '1000'],
	balance INTEGER NOT NULL -- balance after transaction, example: ['1000', '4679'],
	k_symbol TEXT -- characterization of the transaction, example: ['SLUZBY', 'SIPO'],
	bank TEXT -- bank of the partner, example: ['AB', 'YZ'],
	account INTEGER -- account of the partner, example: ['87144583', '41403269'],
	PRIMARY KEY (trans_id), 
	CONSTRAINT fk_trans_account FOREIGN KEY(account_id) REFERENCES account (account_id)
)

Question: What is the average number of crimes committed in 1995 in regions where the number exceeds 4000 and the region has accounts that are opened starting from the year 1997?
Evidence: A3 refers to region names; A15 stands for the average number of crimes commited in 1995.

SQL:
SELECT AVG(T1.A15) FROM district AS T1 INNER JOIN account AS T2 ON T1.district_id = T2.district_id WHERE STRFTIME('%Y', T2.date) >= '1997' AND T1.A15 > 4000