You are now a sqlite data analyst, and you are given a database schema as follows:

    【Schema】
    【DB_ID】 donor
【Schema】
# Table: donations
[
(donationid:TEXT, Primary Key, Examples: [000000a91a14ed37bef82e125c102e77]),
(projectid:TEXT, Examples: [ffffac55ee02a49d1abc87ba6fc61135]),
(donor_acctid:TEXT, Examples: [22cbc920c9b5fa08dfb331422f5926b5]),
(donor_city:TEXT, Examples: [Peachtree City, Rockville, Salem]),
(donor_state:TEXT, Examples: [GA, MD, IN]),
(donor_zip:TEXT, Examples: [30269, 20853, 47167]),
(is_teacher_acct:TEXT, Examples: [f, t]),
(donation_timestamp:DATETIME, Examples: [2011-08-25 14:27:34.807000]),
(donation_to_project:REAL, Examples: [42.5, 26.83, 55.35]),
(donation_optional_support:REAL, Examples: [7.5, 4.73, 0.0]),
(donation_total:REAL, Examples: [50.0, 31.56, 55.35]),
(dollar_amount:TEXT, Examples: [10_to_100, under_10, 100_and_up]),
(donation_included_optional_support:TEXT, Examples: [t, f]),
(payment_method:TEXT, Examples: [no_cash_received, creditcard, paypal]),
(payment_included_acct_credit:TEXT, Examples: [f, t]),
(payment_included_campaign_gift_card:TEXT, Examples: [t, f]),
(payment_included_web_purchased_gift_card:TEXT, Examples: [f, t]),
(payment_was_promo_matched:TEXT, Examples: [f, t]),
(via_giving_page:TEXT, Examples: [f, t]),
(for_honoree:TEXT, Examples: [f, t]),
(donation_message:TEXT)
]
# Table: projects
[
(projectid:TEXT, Primary Key, Examples: [00001ccc0e81598c4bd86bacb94d7acb]),
(teacher_acctid:TEXT, Examples: [42d43fa6f37314365d08692e08680973]),
(schoolid:TEXT, Examples: [c0e6ce89b244764085691a1b8e28cb81]),
(school_ncesid:TEXT, Examples: [063627006187, 483702008193, 410327000109]),
(school_latitude:REAL, Examples: [36.57634, 32.911179, 45.166039]),
(school_longitude:REAL, Examples: [-119.608713, -96.72364, -122.414576]),
(school_city:TEXT, Examples: [Selma, Dallas, Colton]),
(school_state:TEXT, Examples: [CA, TX, OR]),
(school_zip:INTEGER, Examples: [93662, 75243, 97017]),
(school_metro:TEXT, Examples: [urban, rural, suburban]),
(school_district:TEXT, Examples: [Selma Unified Sch District]),
(school_county:TEXT, Examples: [Fresno, Dallas, Clackamas]),
(school_charter:TEXT, Examples: [f, t]),
(school_magnet:TEXT, Examples: [f, t]),
(school_year_round:TEXT, Examples: [f, t]),
(school_nlns:TEXT, Examples: [f, t]),
(school_kipp:TEXT, Examples: [f, t]),
(school_charter_ready_promise:TEXT, Examples: [f, t]),
(teacher_prefix:TEXT, Examples: [Mrs., Mr., Ms.]),
(teacher_teach_for_america:TEXT, Examples: [f, t]),
(teacher_ny_teaching_fellow:TEXT, Examples: [f, t]),
(primary_focus_subject:TEXT, Examples: [Literature & Writing, Literacy, Social Sciences]),
(primary_focus_area:TEXT, Examples: [Literacy & Language, History & Civics, Math & Science]),
(secondary_focus_subject:TEXT, Examples: [College & Career Prep]),
(secondary_focus_area:TEXT, Examples: [Applied Learning, Literacy & Language, Math & Science]),
(resource_type:TEXT, Examples: [Books, Technology, Other]),
(poverty_level:TEXT, Examples: [highest poverty, high poverty, moderate poverty]),
(grade_level:TEXT, Examples: [Grades 6-8, Grades PreK-2, Grades 3-5]),
(fulfillment_labor_materials:REAL, Examples: [30.0, 35.0, 9.0]),
(total_price_excluding_optional_support:REAL, Examples: [555.81, 296.47, 430.89]),
(total_price_including_optional_support:REAL, Examples: [653.89, 348.79, 506.93]),
(students_reached:INTEGER, Examples: [32, 22, 17]),
(eligible_double_your_impact_match:TEXT, Examples: [f, t]),
(eligible_almost_home_match:TEXT, Examples: [f, t]),
(date_posted:DATE, Examples: [2014-05-12])
]
# Table: essays
[
(projectid:TEXT, Examples: [ffffc4f85b60efc5b52347df489d0238]),
(teacher_acctid:TEXT, Examples: [c24011b20fc161ed02248e85beb59a90]),
(title:TEXT, Examples: [iMath]),
(short_description:TEXT),
(need_statement:TEXT),
(essay:TEXT)
]
# Table: resources
[
(resourceid:TEXT, Primary Key, Examples: [0000037fecc4461faf0e49328ae66661]),
(projectid:TEXT, Examples: [ffffc4f85b60efc5b52347df489d0238]),
(vendorid:INTEGER, Examples: [430, 82, 767]),
(vendor_name:TEXT, Examples: [Woodwind and Brasswind]),
(project_resource_type:TEXT, Examples: [Technology, Supplies, Other]),
(item_name:TEXT),
(item_number:TEXT, Examples: [249995.001, BB11216668, VX748]),
(item_unit_price:REAL, Examples: [149.0, 148.0, 69.95]),
(item_quantity:INTEGER, Examples: [4, 1, 2])
]
【Foreign keys】
donations.projectid=projects.projectid
resources.projectid=projects.projectid

    【Question】
    From the total amount of donation to projects, what is the percentage of the amount is for school projects located in the rural area? located in the rural area refers to school_metro = 'rural'; percentage = divide(sum(donation_to_project), sum(donation_to_project where school_metro = 'rural'))*100%

    【Evidence】
    located in the rural area refers to school_metro = 'rural'; percentage = divide(sum(donation_to_project), sum(donation_to_project where school_metro = 'rural'))*100%

    Please read and understand the database schema carefully, and generate an executable SQL based on the user's question and evidence. 

SQL: SELECT CAST(SUM(CASE WHEN T2.school_metro = 'rural' THEN T1.donation_to_project ELSE 0 END) AS REAL) * 100 / SUM(donation_to_project) FROM donations AS T1 INNER JOIN projects AS T2 ON T1.projectid = T2.projectid